Just when Joe Mauer started swinging the bat as well as he has all season, sore quadriceps in both legs have slowed his roll.

Mauer was not in the starting lineup on Thursday for the fourth time in the Twins’ past nine games. In that time he has played first base just twice.

After going 3-for-4 with a home run against Atlanta on Aug. 16, Mauer was batting .394 over a 20-game stretch, raising his season average to .284. In that game he scored from first on a Trevor Plouffe double and has been in and out of the lineup since.

“It has lingered a little bit,” Twins manager Paul Molitor said. “I think it was a little more problematic than he was leading on.”

Molitor has looked for games against lefthanded starters as opportunities to give Mauer time off. The soreness affects his running and his first step when he plays defense.

He thinks he will have Mauer available Friday to face Toronto — but another lefty will be on the mound in Francisco Liriano.

“I’m hopeful and somewhat optimistic,” Molitor said.

Sano back at third?

Miguel Sano ended an 0-for-24 skid on Wednesday with a single. On Thursday, he doubled twice in the Twins’ loss to the Tigers.

“Trying to get him going,” Molitor said. “He’s a big part of what we do offensively, if we are going to compete.”

Sano, bothered by a sore right elbow, served as the DH for the 11th time in his past 12 starts.

But he said that he’s getting better and wants to return to third base this weekend.

“I’ve been icing it and going through treatment that the trainers put me through,” Sano said. “I feel much better, so hopefully in Toronto I can test it out and see how it feels.”

Molitor sees Sano’s age, 23, and strong arm and feels it’s too early to not have him play a position. The right field experiment didn’t work out, and Sano moved to third when Plouffe landed on the disabled list. He has committed 12 errors there.

“I don’t think it will be a huge difference-maker in terms of him being able to come back and be a third baseman,” Molitor said. “It just would be nice to see him out there continuing to gain experience.”

Sano likely will share third with Plouffe while DHing as well.

Facing the Jays again

Pat Dean is making an emergency start Friday, and it’s coming against a team he’s familiar with.

Dean made his first major league start May 21 at Target Field against Toronto, and he held the Blue Jays to two runs over six innings in a 5-3 Twins victory. Jose Bautista homered off of him, but Bautista does that to everyone.

“The biggest thing is doing what I did the last time I faced them,” Dean said. “Stay aggressive with them and not be intimidated or start second-guessing yourself. That’s when things start to unravel.’’

Park has surgery

Byung Ho Park had surgery to repair a tendon in his right middle finger. Hand specialist Dr. Tom Varecka performed the procedure. Park will remain in the Twin Cities for the time being to begin his rehabilitation.