SEATTLE — It took awhile longer than usual for Hector Santiago to warm up on Tuesday night, and he didn't pitch very well, lasting only 2 2/3 innings. When he reported feeling only so-so after playing catch on Wednesday, the Twins decided to give him some rest.

"He's had a little trouble getting loose," Twins manager Paul Molitor said. "We don't think it's anything major, but we have a lot of season to go. … It's the right thing to get him back to 100 percent."

Santiago was placed on the 10-day disabled list with a sore left shoulder before Wednesday's game with the Mariners, and he'll return to Minneapolis to be examined by team doctors, rather than travel with the team to San Francisco this weekend. Molitor said he's still considering who will take Santiago's start against the Giants on Sunday.

One possibility, albeit maybe a long shot: newcomer Chris Heston, who will arrive at Safeco Field, airlines willing, sometime about halfway through tonight's game. Heston, claimed off waivers from the Dodgers' minor league team, hasn't pitched since June 1, and given his travel day, it's not likely he will make his Twins debut tonight. But it's possible, Molitor said.

Meanwhile, the Twins will try to even the series behind Adalberto Mejia, another former Giant, who faces Seattle's Yovani Gallardo. Molitor said the young lefthander is feeling more comfortable about pitching in the major leagues, and he's interested to see how he approaches the Mariners' hot lineup.

Kennys Vargas is back in the Twins' dugout, having arrived to fill in for Jorge Polanco, who was placed on the bereavement list today following the death of his grandfather. Given the distance involved, Molitor said it's not clear when Polanco might return, but he encouraged the young shortstop to take as long as he needs.

Here are the lineups for tonight's game in Seattle:

TWINS

Dozier 2B

Mauer 1B

Sano 3B

Kepler RF

Grossman DH

Castro C

Buxton CF

Rosario LF

Adrianza SS

Mejia LHP

MARINERS

Heredia CF

Smith SS

Cano 2B

Valencia 1B

Seager 3B

Motter LF

Gamel RF

Zunino C

Ruiz DH

Gallardo RHP