Middlebrooks, 25, sustained the injury in the first inning of last night's game against Detroit when he attempted to field a line drive. In 21 games for Boston this year, all starts at third base, he has hit .197 (14-for-71) with three doubles, two home runs, and nine RBI. This is Middlebrooks' second stint on the disabled list this season, after missing 19 games from April 5-19, due to a right calf strain.
Holt, 25, returns to the Red Sox for his third major league stint of the 2014 season. With Pawtucket this year, he has hit .315 (34-for-108) with eight doubles, two triples, one home run, seven RBI, and 21 runs scored in 27 games. Entering play today, his batting average ranks sixth best among all International League players, and he is tied for the club lead in runs scored. In seven games for Boston this season, Holt has batted .348 (8-for-23) with one triple and four RBI. Defensively, he appeared at third base in seven games, all starts.