From his debut in 1999 to 2003, Melvin Mora was known as a utility player, playing all three outfield positions, shortstop, and second base. In 2004, the Orioles made Mora their everyday third baseman, a position he occupied through 2009.
Mora was signed out of Venezuela in 1991. After spending seven years in the Astros minors system and couple of months in CPBL's Mercuries Tigers, he signed as a free agent with the Mets in 1998 and made his major league debut in the 1999 season. With his ability to play all three outfield positions, shortstop, second base and third, Mora was considered a valuable man to have around.
In 1999, he scored the winning run of the final game of the year for the Mets on a wild pitch by the Pirates' Brad Clontz, which propelled the Mets to a one-game playoff with Cincinnati, which they won.
Melvin Mora was traded by the Mets to Baltimore on July 28, 2000, with two minor league players and Mike Kinkade for shortstop Mike Bordick.
Used as a utility player in Baltimore, Mora showed promise and hints of ability to contribute as an everyday player but struggled to break through. Things changed when an injury-depleted Orioles team used Mora almost exclusively in left field, and Mora responded with the best stretch of his career. He reached base in 32 straight games while using a 23-game hitting streak to temporarily become the American League batting leader. Finally excelling as a hitter, Mora was chosen for his first All-Star selection. Mora's season was cut short due to injuries (a bruised wrist and a partially torn ligament in his left knee), but finished with a .317 batting average, 15 home runs, and a .418 on-base percentage in 96 games.
Mora's 2003 season proved that he could be a consistent hitter at the major league level. In 2004, Mora became the Orioles' regular third baseman and enjoyed his most productive season in the majors. Mora hit a career-high .340, finishing second in the AL batting race to Ichiro Suzuki's .372 mark; led the league hitters in on-base percentage (.419); ranked 5th in slugging average (.562) and OPS (.981); 6th in runs (111), doubles (41) and times on base (264); 8th in hits (187), and 9th in total bases (264). His 27 home runs and 104 RBI were also career-highs, while leading his team in batting average, runs, on-base percentage, slugging average and OPS. At third base, he improved and became more consistent as the season wore on.
In 2005, Mora once again hit 27 home runs, although his batting average and on-base percentage dropped. On May 19, 2006 Mora agreed to a three-year, $25M deal that included a no-trade clause because Mora did not want to move his family to another city.
In 2006, Mora's home run total dropped to 16, and again dropped in 2007 to 14. Mora also saw his batting average fall to .274 for both seasons.
Mora was named American League Player of the Month for August 2008. Mora batted .418 (41-for-98) with 8 home runs and had a MLB leading 32 RBIs in 24 games. He posted a .765 slugging percentage and a .455 on-base percentage, with 17 extra-base hits, including eight doubles. Mora had a 13 multi-hit games in August 2008 and maintained an 8-game hitting streak from August 1–10. On August 17 at Detroit, Mora went 5-for-6 with two doubles, 2 home runs, 4 runs scored and 6 RBIs during a 16–8 Orioles win. Overall, Mora had five games in August in which he collected four-or-more RBIs. Mora injured his hamstring on August 29, 2008, missing the final games of his impressive month.
On September 18, 2009, Brooks Robinson made a rare appearance at Camden Yards to honor Mora for moving into second all-time in games played at third base by an Oriole (behind only the Hall of Famer Brooks, himself). He presented Melvin with the third base from the game he moved into second.
In 2009, he led all major league starting third basemen in range factor, at 3.14.
Mora's option was declined by the Orioles on October 29, 2009.
On February 5, 2010, the Colorado Rockies signed Mora to a one-year, $1.275 million contract. He played in 113 games for the NL West third place Rockies (83-79) and batted .285 with seven home runs and 45 RBI.
Mora signed a one-year $2.35 million contract with the Arizona Diamondbacks on December 6, 2010. He was expected to replace Mark Reynolds as the starting third baseman. Mora missed a few days of spring training as a precautionary measure despite not having any serious injuries after his automobile was struck from behind by another vehicle on Arizona State Route 101 on March 7, 2011. He was in the starting lineup on Opening Day, scoring a run while going hitless in five at-bats in a 7–6 victory over the Rockies at Coors Field on April 1. His playing time eventually was limited due to the emergence of Ryan Roberts. After a 6–2 loss to the Cleveland Indians at Chase Field on June 29 in which he struck out as a pinch hitter for Zach Duke with one out and a runner on first base in the fifth inning, he was given his unconditional release effective the following day. He batted .228 with no home runs and 16 RBI in 42 games with the Diamondbacks. He allegedly officially announced his retirement as an active player on December 29, 2011, though in mid-January, Mora corrected that claim by saying he still wished to play in 2012.
Melvin Mora agreed to represent his native country, Venezuela, in the 2006 World Baseball Classic, joining fellow Venezuelan major Leaguers Bobby Abreu, Edgardo Alfonzo, Miguel Cairo, Omar Vizquel, Carlos Guillén, Johan Santana, Freddy García, Carlos Silva, Carlos Zambrano, Víctor Zambrano, Juan Rivera, and Francisco Rodríguez. He later pulled out after being denied the third-base position in favor of Miguel Cabrera.Twice All-Star (2003, 2005)
Twice American League Player of the Month (May 2004, August 2008)
First player to hit a home run off the top of the foul pole at Camden Yards
When he was six years old, his father was murdered in front of him in Venezuela by men who mistook him for somebody else.
On July 28, 2001, Mora's wife Gisel gave birth to quintuplets at Johns Hopkins Hospital in Baltimore, Maryland. The babies, three girls and two boys, were named Genesis Raquel, Jada Priscilla, Rebekah Alesha, Christian Emmanuel, and Matthew David. They also had an older daughter Tatiana before the quintuplets were born. The family resides in Fallston, Maryland.
In the Orioles media guide, Mora stated his most embarrassing moment as a player came in his rookie year in 1999 when, knowing little English, he thought his manager Bobby Valentine had told him to go to left field when he was actually being told to go to second base.
Mora was naturalized as a United States citizen in Baltimore on May 10, 2017. He holds U.S.-Venezuela dual citizenship.