It's a huge blow to a Twins team that's already missing a few key players because of injuries. Considering Mauer is the defending batting champion and plays a vital position, the loss is even bigger.
Mauer has been slowed by the injury in recent days. He didn't start a game last week in Detroit because of soreness, but entered as a pinch hitter later in the game. More problems came on Saturday when he leg tightened up on him while running the bases during batting practice.
An MRI of his leg revealed the strain. Catcher Chris Heintz was called up from Class AAA Rochester to replace Mauer on the roster and provide a backup for Mike Redmond, who will have to assume the catching duties until Mauer returns.
Twins outfielder Michael Cuddyer has been slowed with a bruised back, so the Twins are missing their Nos. 3 and 4 hitters.
"It's never good to be sitting out games, but especially with Cuddy out already," Mauer said. "And we're a little banged up as a whole. You want to be out there every day."
Last Game:RED SOX 4, TWINS 3: Twins right-hander Sidney Ponson gave up four runs early and the Twins never recovered as they lost two of three games at home to the Red Sox. Ponson, who lasted just 5 1/3 innings, had a chance to get out of the fifth with only a 2-0 deficit but threw wildly to second on a potential double play ball, allowing a run to score. Jason Varitek drove in a run two batters later to make it 4-0. The Twins got within 4-3 in the seventh on a two-run single by Jason Tyner and RBI single by Torii Hunter, but an injury-depleted Twins lineup couldn't score after that. The Twins have lost four of their last five and 10 of their last 16.
BY THE NUMBERS: 7 -- the Twins' number of come-from-behind wins this season through May 6.
QUOTE TO NOTE: "He's sore -- really sore. During the game I asked him, 'If we have an emergency here, are you going to make it?' And he said, 'I can go catch, but who is going to run for me?'" -- Twins manager Ron Gardenhire on Joe Mauer's left quad injury.