Turner was drafted ninth overall, in the first round of 2009 Major League Baseball Draft by the Detroit Tigers. Turner signed a major league contract with the Tigers for a guaranteed $5.5 million, with the potential to reach $7 million. Turner is represented by sports agentScott Boras. He was placed on the Detroit Tigers 40-man roster in November 2009. Prior to the 2010 season, Turner was named the 26th best prospect in baseball according to Baseball America The same publication lists Turner as the No. 1 prospect in the Tigers system. Turner began his career with the Tigers' minor league A level affiliate West Michigan Whitecaps. On June 23, 2010 Turner was promoted to the Tigers' high A affiliate, the Lakeland Flying Tigers. Turner began the 2011 season at the Tigers' Double-A affiliate, the Erie SeaWolves. He was named the No. 1 Tigers prospect by Baseball America, who also stated he had the best curveball and changeup in the system. Overall, Turner was listed as the 21st best prospect in baseball by Baseball America, and the 15th best by MLB.com On July 30, 2011, Turner was recalled to replace Charlie Furbush, who was traded to the Seattle Mariners. He was sent down to the minor leagues after his debut, but was brought back up to the major league club when the major league rosters expanded to 40 players on September 1.
Miami Marlins
On July 23, 2012, Turner, Rob Brantly, and Brian Flynn, were traded from Detroit to the Miami Marlins for Aníbal Sánchez and Omar Infante. During the rest of the 2012 season, Turner compiled a 1–4 record with a 3.38 ERA, 0.98 WHIP and 29 strikeouts in seven starts. Turner posted a 3.74 ERA in 20 starts for the 2013 Marlins, but only went 3–8 as his team finished dead last in runs scored that season. After pitching to a 4–7 record and a 5.97 ERA in 20 games in 2014, he was designated for assignment on August 5, 2014.
Chicago Cubs
On August 8, 2014 the Chicago Cubs acquired Turner from the Marlins for two minor league relief pitchers. He pitched in eight games with the Cubs, with a 2–4 record and 6.49 ERA. Turner was diagnosed with a flexor strain and bone bruise on March 10, 2015, and placed on the disabled list six days later. He was moved to the 60-days disabled list on April 19.
Turner was claimed off waivers by the Chicago White Sox on October 27, 2015. On December 2, they did not tender him a contract for the 2016 season, making him a free agent. Two days later, he re-signed with the White Sox on a one-year contract for $1.5 million. After left handed starter Carlos Rodon landed on the disabled list, the White Sox called up Turner to take his spot in the rotation. After allowing 12 runs in 2 starts for Chicago, Turner was sent to the bullpen.
Washington Nationals
Turner became a free agent after the 2016 season and signed with the Nationals on a minor league deal, which included an invitation to spring training. He did not make the Opening Day roster but had his contract purchased from the Class-AAA Syracuse Chiefs of the International League for a spot start against the Colorado Rockies on April 24. Turner remained with the team, transitioning to a bullpen role. He earned his first win with the Nationals on May 3, pitching four scoreless innings in relief against the Arizona Diamondbacks. The Nationals designated Turner for assignment on July 1, 2017, after he gave up five runs in 3⅔ innings against the St. Louis Cardinals in relief. In total, Turner posted a 5.08 ERA in his first stint with the Nationals, striking out just over five batters per nine innings. After Turner was outrighted to Syracuse, he joined the pitching rotation there until the Nationals again selected his contract July 17, 2017, to serve as a long relief option while they awaited the activation of newly acquired relievers Sean Doolittle and Ryan Madson. He was called up again, on July 17, 2017, to provide pitching depth. He was once again DFA'd on July 18, 2017, without making an appearance for the team.
Second stint with the Miami Marlins
Turner signed a minor league contract with the Miami Marlins on December 19, 2017. His contracted was purchased by the Marlins on March 29, 2018, and he was assigned to the Opening Day roster. He was designated for assignment on April 8, 2018. Turner cleared waivers and was outrighted to the New Orleans Baby Cakes. He was released from the organization on June 2, 2018.
Second stint with the Detroit Tigers
On June 5, 2018, Turner signed a minor league contract with the Detroit Tigers. Turner's minor league contract was purchased by the Tigers on August 7, 2018, when he started in place of Mike Fiers, who had been traded to the Oakland Athletics the day before. In his first start for the Tigers, he allowed seven runs, five of which were earned-runs, on six hits in just one inning. He was designated for assignment by the Tigers on August 10. After clearing waivers, Turner was sent outright to the Toledo Mud Hens on August 13, 2018. The Tigers had intended to purchase Turner's minor league contract six days later and have him start on August 19, 2018, due to injuries but MLB rules state a player has to wait ten days after being designated for assignment before being called up. He declared free agency on October 3, 2018.
Kia Tigers
On November 18, 2018, Turner signed with the Kia Tigers of the KBO League. He became a free agent following the season.
Pitching style
Turner throws four main pitches: a four-seam fastball, a sinking two-seam fastball, a curveball and a slider. He also throws a rare changeup, which is used almost exclusively against left-handed hitters. He often relies on the curveball with two strikes in the count.
