Published: Jul 31, 2012 9:04 PM EDT
Updated: Aug 01, 2012 6:31 AM EDT

BOSTON (AP) - Josh Beckett left the Boston Red Sox game in the third inning on Tuesday night with what the team called a back spasm,

Beckett motioned for the trainer to come to the mound after walking Miguel Cabrera to force in the first run against the Detroit Tigers. His lower left back was checked and Beckett walked slowly off the mound. He was replaced with two outs by Clayton Mortensen, who retired the next batter, Prince Fielder.

Beckett began the game with a 5-9 record and a 4.57 ERA with a 1-5 mark in his previous nine starts. His name was mentioned in trade speculation before Tuesday's 4 p.m. deadline for non-waiver deals.

He retired the first eight batters before allowing an infield single, hitting a batter and walking two.