SEATTLE — Though Monday marked a significant step forward from all three injured Astros, no target date is set for the return of George Springer, José Altuve or Aledmys Díaz.

After taking a recovery day on Sunday in Oakland, each man ran on the field and hit in the batting cage on Monday at T-Mobile Park. Altuve and Díaz participated in an infield drill with bench coach Joe Espada, too, according to manager A.J. Hinch.

"They all look great," Hinch said. "It's fun to see these guys rehab with a lot of confidence. I don't see them guarded. I don't see them worried. I don't see them tentative at all. Springer, especially, is the one who has taken the biggest leap forward. That's a good sign."

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Hinch said Sunday that all three players will require a rehab assignment, all but ruling out a return during this four-game series in Seattle.

Holding a nine-game lead in the American League West and a 40-20 record entering Monday's opener against the Mariners offers opportunity for a slower pace. Not counting Monday's game, Houston had been without all three players for the last six games, a stretch in which they went 5-1. Altuve has missed 21 games. The Astros have lost only five of them.

Springer's leap has been noticeable throughout the last week. Initially, the organization feared he sustained a far more serious injury on May 24. On Monday, Hinch marveled at how the energetic outfielder "was flying" during his pregame work.

Altuve, who is trying to build up strength in his sore, surgically repaired right leg, ran "with as much confidence as I've seen," Hinch said. Altuve took batting practice on the field at T-Mobile Park before the game, too.

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When that may lead to a minor league rehab assignment is unknown. Hinch hinted that the trio will be measured and gauged more accurately when the team returns home to Minute Maid Park on Friday.

"They're going to do everything at full speed before we send them out," Hinch said.

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