"What we did is tried to balance out the bench a little better and give us a little more versatility as we're moving forward," manager Bobby Valentine said. "[We] brought up a very versatile left-handed hitter [in] Nate Spears and a good defensive right-handed hitter in Jason Repko."
Che-Hsuan Lin was recalled prior to Saturday's 13-5 rout of the Rays, but the outfielder was optioned back to Triple-A Pawtucket after the game to clear one spot on the Sox's active roster.
Michael Bowden, who earned a bullpen job when camp broke, and catcher Luis Exposito, who was with Pawtucket, were both designated for assignment. The moves cleared two spots on the 40-man roster and another on the active roster.
Repko started in center Sunday, batting ninth. He hurt his right leg a week ago, which was part of the reason the Red Sox didn't make a roster move to add another bat after Jacoby Ellsbury partially dislocated his right shoulder on Friday.
"I banged the side of my leg sliding about a week ago," said Repko, who played for Pawtucket on Saturday after sitting since April 7. "[They] just held me out until it got better. I played yesterday."
A player designated for assignment must be traded, released or if he clears waivers, assigned to the Minors within the next 10 days.
There's a good chance that teams will be interested in Bowden. The 25-year-old was the 47th overall pick in the 2005 First-Year Player Draft. He made his Major League debut in 2008, and lifetime has a 5.61 ERA in the Majors, with 37 runs allowed, 48 strikeouts and 23 walks in 59 1/3 innings.
Bowden last pitched Tuesday in Toronto, letting up one run in two innings on a homer by Edwin Encarnacion. Bowden struck out three.
"Even Michael's performance the other day, there was one loud sound, but he made good pitches," manager Bobby Valentine said. "His split was coming and the angle of his fastball was developing. I think Mike can pitch at the Major League level, but life isn't always fair and timing isn't always what you want it to be."