Branyan was a 1994 graduate from Stratford Academy. His high school fostered such athletic talent like professional football player Le Kevin Smith and professional golfer Peter Persons. Branyan was selected as an All-Georgia State player in both 1993 and 1994. He was drafted out of Stratford Academy in the 1994 Major League Baseball draft by the Cleveland Indians in the seventh round (185th pick overall).
Branyan began his professional career with the rookie-level Burlington Indians of the Appalachian League in 1994. He batted .211 with 10 doubles, five home runs and 13 RBIs in 55 games. The next two seasons, 1995 and 1996, Branyan played with the Class-A Columbus RedStixx of the South Atlantic League. He was named the South Atlantic League Most Valuable Player in 1996 after he set a league record for most home runs in a single season, with 40. The previous record was held by Mike Simms who hit 39 home runs in 1987. He was second in home runs and ninth in RBIs (with 106) in all of minor league baseball in 1996. He was named the Indians' 1996 Minor League Player of the Year (receiving the "Lou Boudreau Award").
In 1997, with both the Class-A Advanced Kinston Indians and the Double-A Akron Aeros, he led all minor league baseball in home runs with 39. Russell Branyan was once considered a top prospect in the Cleveland Indians organization, being compared to Mark McGwire. In 1998 a strained tendon in his right wrist kept him on the disabled list for most of the season. In 1999 for the Bisons, he batted .208 and hit 30 home runs.
Branyan was first called up to the Cleveland Indians in 1998. In his major league debut on September 26, 1998, Branyan went 0-for-4. The next season, 1999, Branyan played 11 games with Cleveland, batting .211 with one home run and six RBIs. Branyan got his first hit (also his first home run) on July 23, 1999 off of New York Yankees' pitcher David Cone. In 2001, Branyan continued his struggles, hitting .238 with 16 homers. After the 1999 season, Baseball America named Branyan as the Indians top prospect. On June 1, 2000 he hit two home runs in one game, the first two home run game of his career. In 2001, an injury to Travis Fryman moved Branyan to third for a good part of the season. He again had a poor average, batting .232, with 20 home runs. In 2002, manager Charlie Manuel wanted Branyan to succeed Fryman full-time, though he was primarily used as a utility player throughout the season. Manuel stated that Branyan should be an everyday player saying, "He's definitely not a guy you want sitting on the bench, because of the timing in his swing." In spring training, Branyan was promised that he would be an everyday player. He hit .205 with just 8 homers before he was traded to Cincinnati for prospect Ben Broussard.
Branyan called the trade to Cincinnati, "a clean slate", stating he had been branded as a home run or strikeout player in Cleveland. He improved his numbers after the trade, but they still remained poor as he played left field opposed to his normal position at third base that was occupied by Aaron Boone. On August 4, 2002, Branyan hit three home runs, two off of Bobby J. Jones and one off of Mike Holtz as the Reds beat the San Diego Padres. He also hit two home runs on September 27, both off Montreal Expos' pitcher Javier Vázquez. He finished the 2002 season to hit a combined .228 with 24 home runs and 151 strikeouts between the Indians and Reds. Branyan was also praised for his improved fielding during his transition to the outfield. At season's end, Branyan played winter ball in the Dominican Republic where on November 18, he injured his shoulder. An examination with the team's physician discovered serious damage, and Branyan underwent arthroscopic surgery on this shoulder on December 3.
Branyan suffered through an injury-plagued season in 2003, appearing in 74 games, including 42 starts, for the Reds. He began the season on the disabled list, recovering from arthroscopic surgery. Branyan was reinstated from the disabled list on May 29. Branyan's shoulder was said to be at less than 100 percent but the Reds reinstated him despite his preference to undergo more rehab. On June 25, Branyan was fined an undisclosed amount after an in game incident against the Chicago Cubs. During the seventh-inning of that game, pitcher Paul Wilson hit outfielder Moisés Alou with a pitch, and during the bottom of the inning Cubs' pitcher Kyle Farnsworth threw inside on Wilson during his at-bat which lead to a fight between Farnsworth and Wilson. Branyan, who was in the dugout, had to be restrained by teammates after a verbal altercation with Cubs' first baseman Eric Karros during the fight between the two pitchers. His home run on June 7, against Toronto Blue Jays' pitcher Jeff Tam was his first of the season. It was also 100th home run hit at the Great American Ball Park. His pinch-hit grand slam off Brooks Kieschnick on July 21 against Milwaukee was his first career pinch-hit home run and third career grand slam. He returned to the disabled list on August 13 with a right ankle sprain he obtained while sliding into the wall chasing a foul ball on hit by San Francisco Giants' second baseman Ray Durham on August 1. After returning from the disabled list on August 28, he started 27 of the Reds' final 29 games of the season. Branyan finished the season with a .216 average, 12 doubles, nine home runs and 26 RBIs. His contract was not renewed at the end of the season.
On January 21, 2004 Branyan signed a minor league contract with an invitation to spring training with the Atlanta Braves. On March 25, Branyan was cut from spring training and assigned to the minor league camp. He began the 2004 season with the Richmond Braves, the Triple-A affiliate of the Braves. He was traded to the Cleveland Indians for a player to be named later and assigned to the Triple-A Buffalo Bisons on April 25.
Branyan was traded to the Milwaukee Brewers on July 26, 2004 from Buffalo for future cash considerations. To make room for Branyan, the Brewers designated outfielder Chris Magruder for assignment. He made' his Brewers debut in a ninth inning pinch-hit appearance that evening. About the trade, Branyan said this,
On July 27, Branyan hit the longest home run in Miller Park history off Chicago Cubs' pitcher Greg Maddux. The ball went an estimated 480-feet. On August 18, Branyan hit two home runs against the Chicago Cubs and drove in all five runs for the Brewers in a loss. Branyan went 3-for-4 in his second multi-home run game of season (ninth of his career) on September 12, against the Cincinnati Reds. Branyan hit .279 with 26 homers and 79 RBIs in 93 games at the Triple-A level in 2004, and posted a .234 batting average with 11 homers, and 27 RBIs in 51 games with the Brewers. He hit six home runs in his first 14 games with Milwaukee. He played 44 games at third base (40 starts), and two games at first base (1 start). On December 21, the Brewers resigned Branyan, avoiding salary arbitration.
Branyan returned to the Brewers in 2005 and went to spring training competing with Wes Helms for the starting spot at third base. He missed a month of the season, from June 2 to July 4, with a fractured middle finger on his left hand. Branyan went 5-for-17 in six rehab games with the Triple-A Nashville Sounds. After Branyan was activated from the disabled list, the Brewers optioned Prince Fielder to the minor leagues to make room for Branyan on the major league roster. Though he was off the disabled list, Branyan was still bothered by injuries throughout the rest of the season. By the end of the 2005 season, Branyan played 59 games at third base, 5 at first base and 3 in left field. On the offensive side, Branyan batted .257 with 11 doubles, 12 home runs and 31 RBIs.
Branyan expressed interest in returning to the Brewers in 2006. He was re-signed by the Brewers on December 20, 2005 but after they acquired third baseman Corey Koskie from the Toronto Blue Jays, Branyan was designated for assignment. Branyan cleared waivers on January 18, and was released by the Brewers.
Branyan signed a minor league contract with the Tampa Bay Devil Rays on January 31, 2006. He attended spring training that year and competed for a spot on the roster as a utility player. Branyan missed more than a week of spring training due to back spasms. He failed to make the 25-man roster out of spring training, and was sent to the Devil Rays' Triple-A affiliate, the Durham Bulls. He did not play in a game for the Bulls, however, as he was called up to Tampa Bay due to an injury to Luis Ordaz on opening day. On May 21, Branyan hit a walk-off home run against Florida Marlins' pitcher Logan Kensing. It was Branyan's first career walk-off home run. With the Devil Rays, he spent the majority of his playing time in right field. Branyan also expressed concerns with the fact he was not an everyday starter. In 64 games for the Devil Rays, Branyan batted .201 with 12 home runs, 10 doubles, and 27 RBIs.
On August 24, 2006, Branyan was traded to the San Diego Padres for minor league pitchers Evan Meek and Dale Thayer. On the trade Branyan said:
Branyan hit two home runs on August 29 against the Arizona Diamondbacks. The first home run in the seventh inning against Brandon Webb went an estimated 422 feet, and the second came in the ninth inning against Jorge Julio went an estimated 456 feet. Branyan hit his fifth home run as a member of the Padres on September 24, against the Pittsburgh Pirates. When recorded, it was the longest in Petco Park history, going an estimated 453 feet. He hit .292 for the Padres with 6 home runs, 9 RBIs, 14 runs scored and 15 walks. He compiled a .416 on-base percentage while slugging .556. He started at third base in 26 of San Diego's final 33 games and committed only 3 errors in 45 total chances. His 18 home runs overall in 2006 were the most he hit in a single season since 2002. At the end of the season it was speculated that Branyan would have a sure spot on the roster out of spring training. On October 30, Branyan's $1,188,016 option was picked up by the Padres.
Going into spring training in 2007, newly acquired Kevin Kouzmanoff was slated for the job at third base. This left Branyan as a bench player going into the season. Branyan addressed the issues stating that he just wanted to play, no matter the circumstances. However, Branyan was seen as a good option if Kouzmanoff failed to produce at third base and at the plate. He got off to a slow start out of spring training.
Branyan was placed on the bereavement list following the death of this father-in-law on April 27. This made room for catcher Josh Bard on the roster. He was activated on May 3 and the Padres sent Pete Laforest outright to the Triple-A Portland Beavers to make room for Branyan on the roster. On May 12, in a win over the St. Louis Cardinals, Branyan hit two home runs. The first was against Kip Wells, and the second against Brian Falkenborg. Branyan hit a go-ahead home run at Wrigley Field against the Chicago Cubs in a 1–0 win on June 16. In 2007, Branyan batted .197 with five doubles, one triple, seven home runs and 19 RBIs in 61 games for the Padres before his release on July 28. The release made room for Scott Hairston on the Padres' roster.
On August 6, 2007, Branyan signed a minor league contract with the Cleveland Indians. He played one game with their Triple-A affiliate, the Buffalo Bisons. On August 9, Branyan was placed on waivers and traded to the Philadelphia Phillies for cash considerations. On August 14, in his first at-bat with the Phillies, Branyan hit a two-run home run against the Washington Nationals, putting the Phillies ahead in the game 3–2.
On August 28, Branyan was designated for assignment by the Phillies. On August 31, he was traded to the St. Louis Cardinals for a player to be named later. During his tenure in St. Louis, Branyan filled in for Scott Rolen, the Cardinals' regular starting third baseman. At the end of the season, Branyan filed for free agency.
On February 20, 2008, Branyan signed a minor league contract with the Milwaukee Brewers. Branyan began the season with the Brewers' Triple-A affiliate, the Nashville Sounds. On May 25, his contract was purchased by the Brewers, and he was added to the active roster. To make room on the roster, the Brewers sent Tony Gwynn Jr. to Triple-A Nashville. About the call-up, Branyan said,
Branyan began the season playing a platoon role with teammate Bill Hall. Hall did not like the shared role, feeling that he should be playing full-time. Branyan expressed no problem with the platoon role, but stated that he understood why Hall disliked the situation. Branyan started the season earning praise from manager Ned Yost and soon saw increased playing time. Later in the season, however, Branyan's playing time was decreased.
He was placed on the 15-day disabled list on August 12 with a right oblique strain. Branyan rehabilitated at the Brewers' spring training facility, and was reinstated on September 23. On May 31, shortly after his return to the majors, he hit a 465-foot home run into the "Dew Deck" in the right-field bleachers of the stadium, helping the Brewers to a 4–1 win. Branyan finished the season with 12 home runs, and 20 RBIs in 132 at bats. He appeared in 50 games with the Brewers, including 35 starts; 33 at third base, and 2 at first base. He became the first player in franchise history to hit 10 home runs while playing 20 or fewer games in a season. He batted .455 with two homers as a pinch hitter.
Branyan signed a one-year contract with the Seattle Mariners on December 3, 2008. The Mariners gave him the starting first base job before spring training. At the end of the 2009 season, Branyan was the team leader in home runs. Branyan stated one of the keys to his success with the Mariners was a vision training program with Chicago ophthalmologist Dr. Barry Seiller. The exercises strengthen eye muscles and improve focus at the plate. The program is one like designated hitter Edgar Martínez used when he played for the Mariners. In Branyan's first at-bat of the game on August 7, he hit a home run. This was his 25th home run on the year, but it also set a new career high. The previous, 24, was achieved during the 2002 season. He has also set career records in RBIs, doubles, hits, runs and total bases in the 2009 season.
On August 9, 2009, Branyan hit a grand slam in the bottom of the sixth inning, this was his first hit in eleven at-bats and his fourth career grand slam. Branyan was often placed in the number two spot in the batting order in 2009 compared to the fourth spot, where managers typically put power hitters. The reason for this was because Branyan expressed discomfort with the cleanup role because of the excessive work load.
Branyan was placed on the disabled list on August 30, with a herniated disk in his back. He had stated that he had been bothered by lower back spasms throughout the season. He left the game against the Kansas City Royals after experiencing pain on a swing and underwent an MRI the next day. On September 27 the Mariners' manager Don Wakamatsu acknowledged it was unlikely that Branyan would be rejoining the Mariners in 2009. However, Branyan was reinstated form the disabled list on September 30 and said there might be a possibility of him playing before the end of the season.
Branyan never played for the Mariners again in 2009 after going on the disabled list, he finished the season with a .251 batting average, 31 home runs, 21 doubles, one triple, 108 hits, 224 total bases in 116 games. On the defensive side he had a .990 fielding percentage with 10 errors (tied for most in the league for a first baseman) in 116 games at first base, all starts.
On November 5, 2009, it was reported that Branyan had shown interest in returning for the Mariners in 2010. There was no comment from Mariners' general manager Jack Zduriencik, but on the possible return, Branyan said:
Branyan rejected a one-year offer from the Mariners on November 10. He stated that the reason for the decline was because he wanted a contract that lasted for more than one year, possibly a two or three-year contract. Branyan also stated that he still wanted to return to Seattle, but would rather test the free agent market than settle for anything less than a two-year contract. On January 7, 2010, the Seattle Mariners traded infielder Bill Hall for first baseman Casey Kotchman. For Branyan, this meant it was unlikely the Mariners would offer him a new contract as Kotchman would be the likely candidate for the starting job at first base, vacated by Branyan. On February 2, 2010, ESPN.com reported that the Florida Marlins had offered a one-year contract to Branyan. On February 5, a conflicting report stated that the Marlins had not offered Branyan a contract. On February 9, Foxsports.com reported that Branyan has drawn interest from both the Cleveland Indians, and the Toronto Blue Jays. Joe Frisaro, writer for MLB.com, reported on February 13, that the Marlins were not interested in signing Branyan. It was reported by Foxsports.com on February 16, that the Tampa Bay Rays, the Boston Red Sox, and the Cleveland Indians were interested in signing Branyan. That day, the Indians offered Branyan a one-year major league contract, according to MLB.com. On February 17, it was reported by Foxsports.com that the Red Sox were no longer interested in Branyan.
On February 19, 2010, Branyan accepted a one-year, $2 million contract with a $5 million option for 2011 from the Cleveland Indians. Slated to be a starter on the club, he was set to begin the season on the disabled list as of March 29, 2010
On June 26, 2010, Branyan was traded back to Seattle for minor leaguers Ezequiel Carrera and Juan Díaz. He was used as Seattle's DH through September.
On February 16, 2011, Branyan signed a minor league contract with the Arizona Diamondbacks with an invitation to Spring training. He made the Diamondbacks' Opening Day roster. To clear up the three-way traffic jam at first base with Juan Miranda and Xavier Nady, Branyan was released on May 21, 2011. Micah Owings was called up to take his spot.
Branyan was signed by the Los Angeles Angels of Anaheim on May 26, 2011. Branyan signed a minor league contract with the New York Yankees for the 2012 season with an invitation to spring training. He was released on August 10, 2012, after playing in 33 games with the Scranton/Wilkes-Barre Yankees. He batted .309 with 11 home runs and spent the greater part of the season on the DL with back issues.
After not playing in 2013, Branyan started 2014 with the Toros de Tijuana of the Mexican League. He signed a minor league deal with the Cleveland Indians on August 29, 2014.
Branyan has three children: daughters Kylie and Quinn, and son Cash. Cash was named after Johnny Cash, of whom Branyan is a fan.
On January 31, 2008, Branyan was arrested for allegedly assaulting his then wife, Jill. According to police accounts, officers were called to a parking lot of a police station after an officer found Jill Branyan sitting alone in her car, crying. The couple had gone to The Cowboy restaurant in Bainbridge, Ohio and reportedly argued on the way home. At some point, Russell Branyan, who was driving, allegedly put his hand on Jill's face, causing her to have a cut lip. The force of the grab caused her to develop a swollen lip and some bleeding. When the couple entered their home, Jill's mother saw the injury and said she, Jill, and the children should leave the home for the evening and go to her house.
Branyan entered a "not guilty" plea in Shaker Heights Municipal Court on February 5, 2008, charged with one count of domestic violence. Branyan's attorney, Philip Kushner, and Pepper Pike prosecutor Jonathan D. Greenberg agreed to terms of a temporary protection order against Branyan that protected Branyan's wife and their two children by temporarily prohibiting Branyan from being within 500 feet of his wife or children among other provisions.
Branyan and his wife later divorced, and on October 30, 2015, Branyan was arrested for breaking into his ex-wife's home in Tennessee while she was asleep. Branyan removed several items from the home and adjusted the thermostat to a very cold temperature.