HOUSTON – The Twins don't appear to be getting far with this new "opener" pitching strategy.

Righthander Trevor May dug a hole the Twins could not climb out of in a 5-2 loss to Houston at Minute Maid Park on Tuesday night. Making the defeat worse was the early departure of Miguel Sano, who was carted off the field in the second inning with what's being described as a lower left leg bruise that initially looked more dire.

In two games, the Twins' "openers" have given up six runs. Houston scored four runs off May in the first inning on an RBI double by Alex Bregman, an RBI single by Tyler White and a two-run home run by Yuli Gurriel.

"I know we'll get a lot of questions and everyone is trying to find out if this is good or bad or sound or whatever," Twins manager Paul Molitor said. He's right, especially when righthander Kohl Stewart — the "primary" pitcher — followed May with five shutout innings.

The way Houston swung at his pitches, May (3-1) said he believed the Astros had him figured out. He wasn't accusing them of cheating; he said he just has to do a better job of changing signs when runners get on second base, because they can tip off hitters.

Bregman and White were on second that inning.

"It didn't go the way we wanted it to go," May said. "There was a little bit of sign figuring out on their end. There were guys at second for quite a while."

The Twins scored on Robbie Grossman's RBI double in the third and Jorge Polanco's homer in the ninth.

What the Twins will remember the most about the game is the sight of Sano grabbing his surgically repaired left leg. Sano had a rod inserted into the leg to stabilize the leg in the offseason.

The injury occurred in the second inning after Sano drew a walk off righthander Justin Verlander to put runners on first and third. Verlander's 0-2 curveball got away from catcher Martin Maldonado and rolled down the third base line. Grossman and Sano tried to advance a base and Maldonado threw to second, where Sano barely beat a tag by Carlos Correa.

Sano's right leg was his lead leg on the play, but his left leg eventually slammed into the bag, and the burly third baseman took his right hand and shoved Correa to get him away from the leg as he fell back in pain.

"That's a lot of mass," Molitor said. "And it hits the ground and there's impact and his leg bent a little funny. I'm sure there was some stress, whether he had the rod in there or not. But I'm speculating that it might have concerned him, knowing the pain was where the work was done."

Sano rolled over three times and was unable to get up as Twins head trainer Tony Leo rushed out to attend to him. After a few moments, a cart was summoned to carry Sano off the field as fans politely applauded.

Initial X-rays were negative, and the Twins announced less than 40 minutes later that Sano has a lower left leg bruise and is day to day. There were no plans for further tests, but he left the park on crutches as a precaution.

"I'm very happy to say that he's doing better than I could have imagined," said Molitor of Sano, who is in a 4-for-46 skid. "At the time, we weren't sure. His first real impact to the area that was worked on last year with the surgery. He was in a lot of pain."