BOSTON (CBS) – Red Sox nation held their breathe after the second inning of Tuesday night’s 6-4 loss to the Royals as third baseman Will Middlebrooks departed with left hamstring tightness.

After the game, Middlebrooks gave them reason to breathe a collective sigh of relief though.

“It’s nothing serious,” Middlebrooks said after the game. “It’s not a big deal, it was just a precautionary thing coming out of the game, so hopefully i’ll be back in there tomorrow. It was just a type of cramping, tightness in the hamstring, so we really didn’t want to mess with it. Wanted to be safe.”

Felger & Mazz: Can Middlebrooks Steal Youk’s Job?

The rookie sensation, who raised his batting average to .409 with a double in the top of the second before leaving, missed Saturday’s 8-2 loss to the Orioles with hamstring cramping. Middlebrooks appeared to be running a bit gingerly when Marlon Byrd followed hi’s double with a single, and then as he scored on a Kelly Shoppach RBI single.

Stats: Red Sox Injuries

In for the injured Kevin Youkilis, Middlebrooks has three home runs, nine RBI and seven extra base hits in five games for Boston.