SAN FRANCISCO -- The Giants were hoping to avoid losing Mike Yastrzemski for an extended period of time, but they’ll now be without their starting right fielder for at least 10 days.

Yastrzemski was placed on the injured list with a left oblique strain as part of a flurry of moves the Giants announced before Wednesday night’s series finale against the Rockies at Oracle Park. Newly acquired outfielder Mike Tauchman was added to the 26-man roster, along with left-handed reliever Sam Selman, while rookie righty Gregory Santos was optioned to the alternate training site in Sacramento.

Yastrzemski hurt his oblique in the Giants’ 4-3 win over the Marlins on Sunday, but the club initially avoided placing him on the IL and expressed optimism that he would return to the lineup after a five- or six-game absence. Manager Gabe Kapler said Yastrzemski was due to be evaluated before Wednesday’s game, though the team evidently determined that the best course of action would be to place him on the shelf.

Kapler and president of baseball operations Farhan Zaidi said Tuesday that the trade for Tauchman, who was acquired from the Yankees in exchange for left-hander Wandy Peralta and a player to be named later, wasn’t a reactionary move to Yastrzemski’s injury, but Tauchman now gives the Giants another left-handed hitter who can play all three outfield spots.

Tauchman, 30, started in center field against Rockies right-hander Germán Márquez in his Giants debut on Wednesday, collecting three hits in a 7-3 win. In five Major League seasons with the Rockies and Yankees, Tauchman slashed .250/.341/.411 with 13 homers and 63 RBIs over 193 games, but the Giants have praised his plate discipline, which should make him a good fit for a San Francisco lineup that takes pride in seeing pitches and wearing down opposing pitchers.

"That's something this team strives to do, and they've been doing a great job of it," Tauchman said. "Just continuing to drown starting pitchers out there and getting into the bullpen, where night after night you're getting into the bullpen early, that adds up over a series, or over a year."

Tauchman said he wasn’t expected to be traded this early into the regular season, but he said he’s looking forward to reuniting with Giants hitting coach Donnie Ecker, who he previously worked with a few years ago in Chicago. Tauchman’s best season came in 2019 with New York, when he hit .277 with an .865 OPS and 13 home runs over 87 games. But his production dipped in '20, when he hit .242 with a .648 OPS and no home runs over 43 games.

"From conversations that I've had, watching video and just kind of analyzing Mike from afar, I think there was a more aggressive pass in there in '19 than there was last year,” Kapler said. “I think we're seeing that aggressive pass show up in a small sample in '21 in New York, so there's some optimism that he's feeling more confident with his swings."

Santos dominated in his Major League debut against the Marlins last Thursday, but he scuffled in his last two appearances and gave up back-to-back home runs to Ryan McMahon and C.J. Cron that sunk the Giants in a 7-5 loss to the Rockies in 10 innings on Tuesday.

While Santos has hit a few bumps in the road, Kapler said he had an encouraging parting message for the 21-year-old prospect.

“Basically that we really, really believe in him,” Kapler said. “I shared with him that good pitchers get hit, and this is an opportunity for him to continue to go work. It’s not an indication that he’s not good enough to pitch at this level and be a valuable part of our bullpen for a really long time.

"I’m trying to convey that these decisions are not punitive. They’re not about failure to perform. Often times, they’re about, ‘We just want to continue your work, and right now, this isn’t the best place for you to do that.’ He was very receptive. I feel confident that he’s going to get the reps and the coaching that he needs, and that he’s going to make an impact in our bullpen this season.”