Matta led the Buckeyes to five Big Ten Conference regular season championships, four Big Ten Tournament titles (2007, 2010, 2011 and 2013), two Final Four appearances (2007 and 2012), and the 2008 NIT Championship. Nonetheless, Matta was fired by Ohio State on June 5, 2017 due to health issues, recent poor team performances, and failure to "win recruiting battles".
A basketball standout for the Cornjerkers at Hoopeston-East Lynn High School in Hoopeston, Illinois, Matta was a two-year starter for the Butler University Bulldogs in three seasons after transferring from Southern Illinois University as a sophomore. He led Butler in assists (100) and three-point field goal percentage (.433) in 1987–88 and in free-throw percentage in 1988–89 (.872). He served as a team captain (one of the Butler tri-captains that year) on Barry Collier's first team in 1989–90 and finished his career in sixth place on Butler's all-time list for free-throw percentage (.800). He earned a B.S. degree from Butler in 1990. Matta enjoyed his Butler career-high point total of 21 points against Xavier University at the Cincinnati Gardens on March 2, 1989.
In total, Matta spent six seasons as a full-time assistant coach at three different universities, helping his squads compile a composite 128–58 (.688) record and make six postseason tournament appearances. He was on the bench in five consecutive conference tournament championship games and won four league tournament championship rings. He was in the NCAA tournament five times as an assistant under four different head coaches and in the postseason National Invitation Tournament once.
Matta began his coaching career at Indiana State University as a graduate assistant under head coach Tates Locke in 1990–91. Matta served as an academic coordinator and administrative assistant at Butler (1991–94) before moving into the full-time coaching ranks.
Matta took his first full-time assistant coaching position under Herb Sendek at Miami University (Ohio) in 1994–95 and helped Miami to a 23–7 record, a Mid-American Conference regular-season championship and a first-round win in the NCAA tournament.
The following year, Matta accepted a coaching position at Western Carolina University under Phil Hopkins and helped the Catamounts to a 17–13 record, the school's first winning record in 10 years. Western Carolina captured the Southern Conference tournament championship and advanced to the NCAA tournament. Matta returned to Miami under new head coach Charlie Coles in 1996–97 and helped the RedHawks to a 21–9 record, the MAC regular season and tournament championships and a berth in the NCAA tournament.
Matta rejoined Butler University's staff in 1997 and helped the Bulldogs to three consecutive 20-win seasons. He established himself as one of the nation's best young coaching prospects during a six-year assistant coaching stint. In his three seasons as Barry Collier's top assistant, Butler compiled a 67–29 (.698) record, won two Midwestern Collegiate Conference tournament championships and one MCC regular-season title, made two NCAA tournament appearances and earned one NIT berth. He served as Butler's primary recruiter.
Matta took over as head coach of Butler when Barry Collier left after the 1999–2000 season to coach at the University of Nebraska. Matta was named 2000–01 Midwestern Collegiate Conference Coach of the Year in his first and only season as head coach at Butler, after leading the Bulldogs to a school record 24 wins. He was also named National "Rookie Coach of the Year" by CBS SportsLine.com and College Insider.com.
Butler was 24–8 under Matta's direction that year with an 11–3 record and an MCC regular season championship, a MCC tournament championship and an appearance in the second round of the NCAA tournament. Butler won 13 of its last 15 games. Eventual NCAA runner-up Arizona ended the Butler run in the second round of the NCAA tournament.
At Xavier, Matta led the Musketeers to three consecutive 26-win seasons, back-to-back Atlantic 10 Conference regular-season championships in 2002 and 2003 and two league tournament titles in 2002 and 2004. Xavier advanced to three NCAA tournaments, including an Elite Eight appearance in 2004 following two second-round trips.
Matta's 26 wins for the 2002–03 season marked the highest win total ever for a second-year Xavier head coach. He also broke the school record for most victories by a Xavier rookie head coach. Xavier's 26–6 record in the 2001–02 campaign set the record.
Matta was named 2002 Atlantic 10 Conference Coach of the Year, while leading the Musketeers to the top regular season finish in the league at 14–2 and an Atlantic 10 Conference Tournament championship. In addition, Matta became the only first-year coach in conference history to ever win both the A–10 regular season and tourney championships.
Matta, a finalist for the 2002–03 Naismith National Coach of the Year Award, began his duties in Columbus on July 7, 2004. No time was wasted preparing for his first season in Columbus, which culminated in a 65–64 victory over undefeated and top–ranked University of Illinois in the regular-season finale at Value City Arena before a packed house and a national television audience. The Buckeyes' final record for the 2004–05 campaign was 20–12, but were ineligible from postseason play.
In the 2005–06 season Matta led the Buckeyes to an outright Big Ten Championship for the first time since 1992, finishing one game ahead of Iowa and Illinois. The Buckeyes' season came to an end during the second round of the NCAA tournament when they lost to Georgetown on March 19, 2006. Their final overall record was 26–6. The Buckeyes were thought to be a year away from competing for the league crown, as they were to add a highly regarded recruiting class, dubbed the "Thad Five", led by center Greg Oden of Lawrence North High School in Indianapolis for the 2006–07 season. The Buckeyes did win the Big Ten and Matta led Ohio State all the way to the national championship game, where they lost to Florida.
During a game against Wisconsin during the 2006-07, Matta's gum fell out of his mouth when he was yelling at the refs. Despite the gum falling on the floor, Matta put it back in his mouth and continued chewing. This incident earned Matta the nickname "Thad Gum".
In the 2007–08 season, Matta's Buckeyes did not make the NCAA tournament. However, they won the 2008 NIT championship, despite playing with four new starters for the second consecutive year.
In 2009, Ohio State went to the NCAA Tournament, but were eliminated in the first round by Siena. In 2010, the Buckeyes won a share of the Big Ten and the 2010 conference tournament title. In the NCAA tournament they beat UC–Santa Barbara in the first round 68–51. The next round they beat Georgia Tech 75–66, but went on to lose to Tennessee in the Sweet 16.
In the 2010–11 season, Matta's Buckeyes were 29–2, ranked #1 in all polls (16–2 in conference play), and won the outright Big Ten Championship. The Buckeyes beat Penn State on March 13 to win their 2nd consecutive Big Ten Tournament title. The Buckeyes were the overall number one seed in the 2011 NCAA tournament and the number one seed in the Eastern bracket, where the Buckeyes won two games in Cleveland before losing to eventual Eastern regional champion Kentucky.
In the 2011-12 season, Matta led Ohio State to its third straight Big Ten Championship shared with Michigan and Michigan State. Ohio State advanced to the Final Four before losing to Kansas in a game the Buckeyes led by nine at halftime. This was the second Final Four appearance in Matta's career.
In the 2012-13 season, Ohio State finished 2nd in the Big Ten Regular Season, one game behind league champion Indiana. The Buckeyes went on to win the Big Ten Tournament in Chicago which was Matta's 4th Big Ten Tournament Championship. The Buckeyes were a 2 seed in the 2013 NCAA Tournament. They lost in the Elite Eight to Wichita State.
On June 5, 2017, Matta was fired as the Buckeyes coach.
Coaches who worked for Matta at Butler have been hired for head coaching positions at University of Iowa and Butler University. Sean Miller worked for Matta for three years at Xavier and was hired as head coach when Matta left, then took the head coaching job at University of Arizona. The success of Matta's staff at Ohio State was acknowledged by Ohio University in 2008, when former Buckeyes Associate Head Coach John Groce was chosen to lead that program. Groce also coached at the University of Illinois Fighting Illini until March 11, 2017. In 2010, former Buckeyes assistant coach Alan Major, who had also worked with Matta at Xavier and Ohio State, was named the head coach at Charlotte. In 2011, Sean's brother Archie Miller, another former Ohio State assistant, got the job at the University of Dayton and then in 2017 was Archie Miller was hired by Indiana University to replace Tom Crean. In 2013, Brad Stevens, a former graduate assistant of Matta's, accepted the head coaching job for the Boston Celtics. Stevens was replaced at Butler by Brandon Miller who had worked for Matta at Xavier and Ohio State. In 2016, long-time assistant Jeff Boals was named the head coach at Stony Brook.