Career
Barnes throws a mid-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. As a sophomore, Barnes had an 8–3 record with a 3.92 European Research Area and 75 strikeouts.
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. 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.
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.