When the Giants placed first baseman Brandon Belt on the 10-day injured list Wednesday, manager Gabe Kapler spoke optimistically about the team’s ability to replace his production because of the way Darin Ruf has performed this season.

Hours after Kapler indicated Ruf would temporarily take over as the team’s starting first baseman, the 35-year-old slugger exited Wednesday’s game in Arizona against the Diamondbacks with an apparent right hamstring injury.

Ruf picked up two hits in three at-bats against the D’backs, but after taking a wide turn around first base following a sixth inning single, he reached for his hamstring and grimaced in pain. Instead of pulling into second base with a double, Ruf limped back to first and immediately exited the game alongside Kapler and a member of the Giants’ training staff.

Jason Vosler, who made his major league debut with the Giants earlier this season, replaced Ruf on the bases and stayed in the game to play first base. Kapler said Vosler, who was activated to take Belt’s roster spot on Wednesday, would likely help the Giants off the bench, but he could see starts at first base if Ruf is required to miss time.

With Ruf out of Wednesday’s game, the Giants were without their top four options at first base as Belt, Wilmer Flores and Tommy La Stella are all on the injured list. Kapler said pregame Flores could come off the injured list as soon as he’s eligible on Saturday, but the injuries continue to pile up and test the Giants’ depth in unexpected ways.

If Ruf needs a stint on the injured list, there are a handful of ways the Giants can adjust.

Outfielder Austin Slater and catchers Buster Posey and Curt Casali all have experience at first base while LaMonte Wade Jr., who is playing at Triple-A Sacramento, has also played first for the major league club this season. Joey Bart, who has limited first base experience in the minors, may also be a candidate for a promotion, but Bart hasn’t played since last Thursday due to groin tightness.