When the Los Angeles Angels play the Houston Astros on Monday night in the opener of a four-game set in Anaheim, Calif., the biggest question is how much Mike Trout will be in center field during the series.

Trout, the two-time American League MVP, left Sunday's 6-3 victory against Seattle after two innings with right calf tightness. The Angels listed him as day-to-day.

Although Trout insisted he felt fine, he was scheduled to undergo an MRI exam on Monday morning.

"I don't feel terrible right now. We'll see how I feel (Monday). I don't think it's that serious," Trout said on MLB.com. "I think they're just being cautious. Calves are tough. You want it to be one or two days and not six weeks."

The Angels, who are five games back in the wild-card chase, can hardly afford to lose Trout, who was hitting .429 with eight homers and 18 RBIs over his previous seven games.

Despite missing time in early April with a right groin strain, Trout is batting .305 with a league-leading 30 home runs and 75 RBIs in 90 games.

Trout said he felt tightness in his calf while tracking down fly balls by Seattle's Domingo Santana and Tim Beckham in the first inning. Trout lined out softly in his only plate appearance in the bottom of the inning, and Kole Calhoun moved from right to center to replace Trout in the top of the third.

"We don't think it's a long-term thing, but we'll know more (Monday)," Angels manager Brad Ausmus said. "He was lobbying to stay in the game."

With Trout out, rookie Matt Thaiss hit a three-run homer in the bottom of the eighth inning, the first home run of his major league career, to snap a 3-3 tie and lead the Angels to a three-game sweep of Seattle, outscoring the Mariners 28-5 in the process. That included a no-hitter Friday in a 13-0 victory when the Angels honored late teammate Tyler Skaggs.

"It's something I'll never forget," Thaiss told MLB.com of his home run. "It was an awesome feeling, especially coming home and seeing the smile on Kole's face. It was really cool."

The Astros, who lead the AL West by six games, pounded Texas 12-4 Sunday as Jose Altuve hit a grand slam and Yuli Gurriel added a two-run shot, both in a seven-run seventh inning. It was Gurriel's 11th home run in his past 15 games.

Houston was scheduled to bring right-hander Brad Peacock off the injured list to start the series opener against the Angels, but instead he was sent back to Houston to be examined by team doctors for "intermittent soreness" in his right shoulder.

"We thought that he was going to be able to pitch. He thought he was going to be able to pitch," said Astros manager AJ Hinch. "We even made some moves that coincided with that idea. ... We want to get him right. It doesn't matter how long he has to be out, as long as he's healthy. It was disappointing news for him and for us."

The Astros will instead use reliever Josh James as an opener and then turn to left-hander Framber Valdez (3-5, 5.28 ERA), who has an 11.57 ERA in the first inning of his five starts this season. Valdez is 2-1 with a 1.69 ERA in three career appearances against the Angels, including two starts.

The Angels are set to start rookie right-hander Griffin Canning (3-5, 4.43). The 23-year-old will be facing the Astros for the first time.

--Field Level Media