"He ran well today," McClendon said prior to Wednesday's series finale with the Rangers. "If all goes well tomorrow, he'll go out on a rehab Friday in Tacoma."
Paxton, on the DL since April 8 with a strained left lat muscle, threw a three-inning simulated game on Tuesday and will throw in the bullpen on Thursday when the team returns to Safeco Field to open an 11-game homestand. If there are no problems Thursday, the 25-year-old southpaw will likely start his own rehab stint in Tacoma on Sunday.
The Mariners aren't setting any firm timeline, but if Paxton throws two Minor League rehab games, he'd then be ready to rejoin the Mariners the first week of June.
Right-hander Taijuan Walker is about a week behind Paxton in his own throwing schedule as he returns from a shoulder impingement that shut him down in mid-April. He'll throw another simulated game at Safeco Field sometime this weekend before a decision is made on when to send him on his own Minor League rehab.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.