June 25. 2013 6:47PM

Red Sox demote Middlebrooks to AAA

BOSTON — The Red Sox demoted struggling third baseman Will Middlebrooks to Triple-A Pawtucket on Tuesday and called up infielder Brandon Snyder.

To make room for Snyder on the 40-man roster, the Sox transferred catcher David Ross to the 60-day disabled list.

Middlebrooks, 24, has hit .192 (39-for-203) with nine home runs, 25 RBIs, 60 strikeouts, nine walks and a .617 OPS in 53 games for Boston this season. He had not played since Thursday, supplanted by Jose Iglesias as the regular third baseman.

Iglesias, 23, entered Tuesday night’s game against visiting Colorado batting .426 (46-for-108) with one home run, seven RBIs, 15 strikeouts, nine walks and a 1.044 OPS.

Middlebrooks missed 16 games while on the disabled list with a lower-back strain from May 24-June 9 and batted .294 (5-for-17) with two home runs, six RBIs, three runs, and four walks over a five-game rehab assignment with Pawtucket from June 4-9.

Snyder, 26, signed with the Red Sox as a minor-league free agent on March 31. In 63 games with the PawSox, he hit .267 (63-for-236) with 16 doubles, one triple, 10 home runs, 37 RBIs, 36 runs and 20 walks while dividing his time between first base and third base. He leads Pawtucket in runs and doubles, and is second on the club in RBI and home runs.

Selected by Baltimore in the first round (13th overall) of the 2005 June draft, Snyder owns a .276 career average (27-for-98) with five doubles, three home runs, 13 RBIs, 14 runs, and six walks in 56 major-league games over parts of three seasons with the Orioles (2010-11) and Rangers (2012).

Snyder was active for Tuesday night’s game against the Rockies, wearing No. 23.

Ross, 36, was placed on the seven-day concussion disabled list after the first game of the Red Sox doubleheader on June 18. He was also on the seven-day concussion DL from May 12-24. In 23 games for the Red Sox this season, he has hit .185 (12-for-65) with two doubles, four home runs and six RBIs.