By Brandon Apter, Sports Talk Philly editor 
The Philadelphia Phillies have given a lot of their Triple-A guys time in the big league bullpen this year, evaluating who might be a potential piece for the future as the season winds down. One of those guys who was very deserving of his promotion this season was 24-year-old right-hander Jesen Therrien. After posting a 1.41 ERA over 57.1 innings between Double-A and Triple-A, Therien was promoted on July 28.
Therrien couldn't replicate the success he had in the minor leagues at the major league level, appearing in 15 games for the Phillies with an 8.35 ERA over 18.1 innings. The Phillies shut him down after an appearance in New York on September 4 and Therrien was placed on the disabled list a little over a week later with a right elbow strain. It turns out the injury was the worst it could be. According to Matt Gelb of the Philadelphia Inquirer, Therrien underwent Tommy John surgery earlier this week and could potentially miss the entire 2018 season with normal recovery time between 12-18 weeks. His velocity was down ever since his promotion to the big league club, 2-3 mph below where he was in the minors.
Gelb mentions the Phillies could remove him from the 40-man roster after the season and then re-sign him to a minor league deal to pay for his rehab in 2018. The Phils added Therrien to the roster for his performance and also the fact that he was going to become a free agent at seasons end.
