The Boston Red Sox today selected right-handed pitcher Sean O'Sullivan to the active major league roster from Triple-A Pawtucket. To make room on the 25-man roster, right-handed pitcher Pat Light was optioned to Pawtucket following yesterday's game against the Los Angeles Angels of Anaheim. O'Sullivan is scheduled to start today's series finale against the Angels at Fenway Park beginning at 1:35 p.m.
 
President of Baseball Operations David Dombrowski made the announcement.
 
O'Sullivan, 28, has made three appearances (two starts) for the Red Sox in one stint with the club this season, going 1-0 with a 7.94 ERA (10 ER/11.1 IP). Signed by the Red Sox as a minor league free agent on December 5, 2015, O'Sullivan has also made 11 starts at Pawtucket, going 6-2 with a 2.79 ERA (22 ER/71.0 IP) and 51 strikeouts against 10 walks. He last pitched on June 25 against Scranton/Wilkes-Barre, allowing four hits and striking out six batters in 7.0 shutout innings without issuing a walk. Originally selected by the Angels in the third round of the 2005 June Draft, he is 12-23 with a 6.03 ERA (210 ER/313.2 IP) in 69 games (54 starts) over parts of seven major league seasons with the Angels (2009-10), Royals (2010-11), Padres (2013), Phillies (2014-15), and Red Sox (2016).
 
Light, 25, has appeared in two games over two stints with the Red Sox this season, allowing eight runs (seven earned) on seven hits in 2.2 innings. In 20 relief outings for the PawSox, he has gone 5-for-5 in save opportunities while posting a 2.05 ERA (6 ER/26.1 IP) and a .161 opponent batting average (15-for-93) with 32 strikeouts, 13 walks, and only one home run allowed. Light has not surrendered a run in 10 minor league appearances since May 21, allowing only six hits with 13 strikeouts in 12.0 innings during that span. Selected by Boston in the supplemental round of the 2012 June Draft, Light converted to a full-time reliever following the 2014 season. In 117 career minor league appearances, including 49 starts, the New Jersey native is 12-18 with 10 saves, a 4.41 ERA (140 ER/286.0 IP), and 236 strikeouts.