Phillies’ Bryce Harper will begin rehab assignment Tuesday at Lehigh Valley

The Phillies announced that Bryce Harper will go to triple-A Lehigh Valley for a rehab assignment starting Tuesday.

The plan is for Harper to DH through Saturday and take Sunday off. If he feels tired during that time, he might take an extra day of rest. Harper has been sidelined since June 25, when his left thumb was broken when he was hit by a pitch from San Diego left-hander Blake Snell.

Phillies interim manager Rob Thomson said that Harper joining the team next Monday in Arizona is a possibility. Harper said on Sunday that he’ll know more once he starts making contact in minor league games. He said he feels the thumb is at “85-90%” strength.

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“I’m getting a lot better,” Harper said on Sunday. “The more I hit, the more I use it, it’s getting better. Yeah, I think we’re happy where we’re at right now. We’ll just progress as we see fit.

“I think our biggest thing is the [mobility] of it, I guess, isn’t there. That’s why I say 85[%], somewhere in there, just because of the [mobility] part of it. But I think the strength and everything like that is there. I think as we progress it’s going to get better and better, I hope.”

Harper took batting practice on the field Monday, as he has been doing most of the past week.

Phillies reliever Seranthony Domínguez had an MRI Sunday that revealed no structural damage to his arm. He was placed on the 15-day injured list that day (retroactive to Aug. 18) with right triceps tendinitis. Thomson said Domínguez likely won’t pick up a ball for five days. It’s possible he can return by Sept. 2, but the Phillies plan to keep monitoring his workload and then make a decision.

Kyle Schwarber did some outfield and change-of-direction drills on Monday afternoon. He hasn’t played left field since Aug. 11, when he exited the game with a mild calf strain.

According to Thomson, Schwarber hadn’t done any outfield drills before Monday, but felt so good running the bases as a DH that he felt comfortable returning soon. Thomson said the best-case scenario is for Schwarber to return to the field on Tuesday, but if there’s anything out of the ordinary, the Phillies will wait a day or two.

The Phillies designated reliever Tyler Cyr for assignment. Cyr was called up from Lehigh Valley after Domínguez was sidelined and gave up a home run to Brandon Nimmo, the first batter he faced in the major leagues, in the ninth inning of Sunday’s 10-9 loss to the Mets. The Phillies selected the contract of left-handed pitcher Michael Plassmeyer from Lehigh Valley to give them some depth. Thomson said Plassmeyer could give them 90-100 pitches if needed.