Matthew D. Barnes (born June 17, 1990) is an American professional baseball pitcher for the Boston Red Sox of Major League Baseball (MLB).
Barnes throws a high-90s four-seam fastball, a curveball, and a changeup. Prior to being drafted by the Red Sox in the first round of the 2011 MLB Draft, he played college baseball at University of Connecticut, where he was named a First Team All-American.
Barnes went to Bethel High School in Bethel, Connecticut. In high school, he was named to the All-State team. Following his high school career, he was not chosen in the Major League Baseball (MLB) Draft. He then enrolled at the University of Connecticut, where he played college baseball for the Connecticut Huskies baseball team in the Big East Conference of the National Collegiate Athletic Association's (NCAA) Division I. As a freshman, he had a 5–3 win–loss record with a 5.43 earned run average (ERA) and 55 strikeouts in 53 innings pitched. As a sophomore, Barnes had an 8–3 record with a 3.92 ERA and 75 strikeouts. In his junior season, Barnes had an 11–3 win-loss record and 1.11 ERA with 97 strikeouts in fourteen games started during the regular season, as the Huskies won their first conference regular season title.
Barnes was twice named to the All-Big East team. Barnes was named Big East Pitcher of the Year in 2011. He was also named to the 2011 College Baseball All-America Teams of the American Baseball Coaches Association and Collegiate Baseball. He was added to the Golden Spikes Award preseason watch list in 2011.
While in college, Barnes played collegiate summer baseball for the Wareham Gatemen of the Cape Cod Baseball League. He also pitched for the United States national baseball team in the 2010 World University Baseball Championship, not allowing an earned run, as the United States won the silver medal.
The Boston Red Sox selected Barnes with the 19th overall selection in the 2011 MLB Draft. He was selected to appear in the 2012 All-Star Futures Game. Entering 2013, Barnes was ranked 38th in the MLB.com Top 100 Prospects list.
The Red Sox promoted Barnes to the major leagues for the first time on September 8, 2014. He finished the rest of the season with the Red Sox, making five appearances with a 4.00 ERA.
On April 23, 2017, Barnes was ejected for the first time in his Major League career for attempting to hit Manny Machado with a pitch. Although the pitch seemed that it struck Machado's helmet, it instead went behind his helmet and hit his bat, triggering a foul ball. The next day, on April 24, Barnes received a 4-game suspension for "intentionally throwing a pitch in the area of the head of Manny Machado."
Barnes began holding an annual baseball clinic at the Newtown, Connecticut, Youth Academy for elementary school students in December 2013, one year after the Sandy Hook Elementary School shooting.