Middlebrooks, who was scratched from last night's lineup, started each of Boston's first four games of the regular season, going 3-for-13 (.231) with two runs, a double, a home run, an RBI, and a walk. The 25-year-old homered off Marco Estrada in Friday's home opener against the Milwaukee Brewers at Fenway Park. Selected by Boston in the fifth round of the 2007 June Draft, the right-handed-hitting Middlebrooks is a career .253 hitter (159-for-628) with 33 doubles, 33 homers, and 104 RBI in 173 major league games from 2012-14, all with the Red Sox.
Holt, 25, has hit .364 (4-for-11) with two doubles, two walks, three runs scored, and a stolen base in three games with Pawtucket this season. Acquired by the Red Sox as part of a six-player trade with the Pittsburgh Pirates in December 2012, the left-handed batter appeared in 26 games with the Red Sox in 2013 and made 17 starts, all at third base. He hit .203 (12-for-59) with two doubles, 11 RBI, and seven walks.