SEATTLE -- Alex Bregman could return to the Astros’ starting lineup as soon as Saturday. The star third baseman, who has been out since suffering a right hamstring injury in Tuesday’s 6-3 win over the Yankees, took a full pregame workout Friday at T-Mobile Park ahead of Houston’s three-game series opener against Seattle.

He is “trending toward” a return Saturday, according to Astros manager AJ Hinch.

“I feel there’s a really good chance,” Bregman said after the Astros’ 10-6 win over the Mariners. 

“It feels really good. I ran 100 percent the last two days, and then I hit today and I fielded, took ground balls. I feel good.” 

Bregman went through a complete running routine in left field that included full sprints under the watchful eye of club athletic trainers, then underwent agility work with Major League strength coach Brendan Verner before taking ground balls to both sides and live batting practice pregame. Bregman showed full mobility while stretching the hamstring on hard-hit choppers to third and while lacing line drives in BP.

Bregman sustained the injury when legging out a passed ball on strike three during the eighth inning on Tuesday, then departed after reaching second on defensive indifference. The prognosis Hinch relayed on Friday was a significant improvement.

“I think he was sore the next day is an understatement,” Hinch said of Bregman’s pain Wednesday, when he underwent treatment and testing at Minute Maid Park. Bregman also completed a full workout during Thursday’s off-day before the club’s flight.

In Bregman’s two-game stead thus far, including Friday, Yuli Gurriel has started at third base while Tyler White has taken over for Gurriel at first. Utility infielder Aledmys Diaz, who the club acquired from the Blue Jays in November, also has experience at third, including 38 games there with Toronto in 2018. Diaz was brought in to create more defensive depth and versatility after the Astros lost Marwin Gonzalez to the Twins in free agency.

Bregman, who is coming off a breakout '18 in which he led the Astros with 30 homers, has picked up where he left off, slashing .341/.440/.488 over 50 plate appearances in 12 games.

Roster move: Guduan up, Valdez down

With three off-days sandwiched in their 10-day weave through the American League West, the Astros have tailored their pitching plans accordingly -- most notably by moving Brad Peacock to the bullpen and going with a four-man rotation.

With Peacock assuming a temporary long-relief role, the Astros optioned Framber Valdez to Triple-A Round Rock and recalled lefty Reymin Guduan in a swap of arms that battled for the final roster spot out of Spring Training.

Valdez ultimately won the battle out of camp largely due to the length he offered, which is no longer an immediate necessity. And Hinch admittedly didn’t deploy Valdez enough over the first two weeks of the regular season to maintain a healthy workload, which the lefty will receive while pitching at Triple-A. Valdez last pitched last Saturday, when he threw a scoreless ninth inning in a 6-0 win against the A’s, one of just two appearances he’s made.

The Astros also favored the matchups that Guduan offers against the Mariners and, specifically, the Rangers, who Houston plays next weekend in Arlington.

Guduan, who appeared in just three big league games in '18, took major strides in camp to create clean, repeatable mechanics that led to a more honed command -- specifically with his slider, which he complements with a four-seam fastball that averages 95 mph, per Statcast.

“You can be erratic with your fastball and he throws hard enough to be dangerous,” Hinch said. “But when you can throw your breaking ball for a strike and over the plate and down, it's very, very uncomfortable for hitters. So part of having that command over the strike zone is you backing up all the way to have a cleaner delivery."