– Righthander Addison Reed finally will start a minor-league rehabilitation assignment Tuesday when he pitches as the opener for Class AAA Rochester.

Reed has been slowed by a left thumb sprain, but he also took the time to focus on his conditioning after posting a 4.50 ERA last season and watching his strikeout rate tumble.

Twins General Manager Thad Levine, who is with the Twins this week in Toronto, said there’s no definite timetable for Reed’s return. While rehabilitation assignments are 20 days for position players, pitchers can take up to 30 days.

“He has been a model player down there in terms of doing everything we’ve asked, from workouts, strength and conditioning, working with our medical staff, being a mentor to young players down there,” Levine said. “It’s time to get him out, see how his arm has responded, and this is the first step.”

Reed started out strong last year after signing a two-year, $16.75 million contract during free agency. He touched 93 mph on the gun, pitched in 15 games during the month of May alone and entered June with a 2.83 ERA.

His season changed in July when he landed on the injured list with a triceps strain. When he returned, his average fastball dipped from 92.4 mph in May to 90.1 in August. He tried adding a sinking fastball to get some more movement.

He pitched on 4⅔ innings in official spring training games this year before being diagnosed with the thumb injury.

Soon, the Twins will get to see if Reed has found his old form.

“I think it’s just as important, in his case, to see how he responds to a little bit better competition at the Triple-A level,” Levine said, “so we didn’t want to burn down too much of his clock at the lower levels.”

Sano must prove it

Levine also pointed out that Miguel Sano, who is at Class AA Pensacola for his rehab assignment, has made progress but the club doesn’t have to rush him to the majors.

Sano is 1-for-11 with a home run in three games since joining the Blue Wahoos. He eventually will move on to Class AAA Rochester when he’s ready, but Sano needs to continue to build his conditioning by playing games.

Sano’s 20-day assignment ends May 20, while the Twins are hosting the Angels. With Marwin Gonzalez able to play third, they can take their time with Sano.

“I think we feel very good about our position-player unit here,” Levine said, “so there’s no artificial sense of urgency that we’re immediately locked into.”