Mike Pelfrey slipped on the mound during the first inning Thursday, and felt something pull in his left groin. The injury didn't affect his performance against the Dodgers — but it came in really handy Friday.

The pulled groin gave the Twins an easy, if temporary, solution to their nagging Pelfrey problem: He went on the disabled list after Friday's game against the Orioles, and he can work his way back to health — and effectiveness, the Twins hope — through some rehab starts in the minor leagues.

"[Pelfrey] said, 'I'm open to whatever you want me to do, but I don't feel comfortable throwing until my groin feels better,' " assistant GM Rob Antony said.

That was all the Twins needed to hear. Samuel Deduno will start Tuesday at Cleveland, and Pelfrey, who has a 7.99 ERA in five starts, can focus on recovering his health — and the velocity he has lost this year.

"He didn't want to say anything. He didn't want to make excuses. But he came in today sore," manager Ron Gardenhire said. "We told him, this might give you an opportunity, first to get your leg well, and then try to figure it out. Get him on a little rehab assignment and try to straighten his pitching out too. It's twofold — get healthy and also try to figure out why his velocity has dropped down 4-5 mph."

Antony said the Twins considered calling up Trevor May from Class AAA Rochester for the open spot but decided Deduno deserved the chance. Pelfrey will be eligible to return May 17, but the Twins can also keep him on a rehab assignment for 30 days.

Hicks out, too

The Twins will be without Aaron Hicks for a while as well. The center fielder, who collided with the center field wall during Thursday's second game, was placed on the seven-day concussion list after he was still "buzzing" a day later, Gardenhire said.

"He took a pretty good whack," Gardenhire said. "This is something you don't mess with."

Sam Fuld will play center in Hicks' absence.

Santana gets call

To replace Pelfrey, the Twins summoned shortstop Danny Santana from Rochester. Santana was hitting .268 and has made progress on some of the sloppy fielding he displayed in spring training, Antony said. Santana is primarily a shortstop — a job that Antony said currently belongs to Eduardo Escobar, and not the slump-ridden Pedro Florimon — but has played outfield in the past, including center.

Oswaldo Arcia is at Rochester on a rehab assignment, but Antony, who spent the past week with the Red Wings, said the young outfielder is not yet ready to come off the disabled list.

Welcome to the majors

Lefthander Logan Darnell fell asleep watching the Twins' 5-hour, 11-minute second game Thursday night. When he awoke around 12:40 a.m., he discovered a half-dozen texts and voice mails on his cellphone. When he saw who sent them — Antony, Rochester manager Gene Glynn, a Red Wings trainer, the Twins' director of travel — "I was pretty pumped," he said.

Sure enough, the message was: Get to Minnesota ASAP. After the Twins needed 12⅔ innings from their bullpen in the doubleheader, they called for reinforcements, and Darnell was the choice.

"It's something you always look forward to happening," said Darnell, a sixth-round draft pick in 2010 who had a 1.69 ERA in four starts with Rochester.

Trying again

Twins left fielder Josh Willingham will try to swing a bat again Saturday in hopes the soreness in the broken bone in his left wrist has subsided. The injury doesn't bother him, he said, except when he swings a bat.