SCOTTSDALE, Ariz. -- The Giants got an unwelcome bit of injury news on Wednesday, as they announced that Keaton Winn has been shut down with mild right elbow soreness.

Winn, who is projected to be the club’s No. 4 starter, underwent an MRI exam on Monday that revealed no structural damage, so he’s expected to rest and receive treatment before being re-evaluated this weekend.

“We’re still trying to formulate some opinions on where we go,” manager Bob Melvin said.

Winn, 26, said he hopes to resume throwing in the next four to five days and doesn’t believe the setback will affect his readiness for the beginning of the regular season. Still, his injury will add a bit more uncertainty to the Giants’ rotation, which is already expected to be without veterans Alex Cobb (left hip surgery) and Robbie Ray (Tommy John surgery) to start the season.

Winn missed the 2021 campaign while rehabbing from Tommy John surgery and spent close to a month on the injured list with elbow trouble last year, but he said he’s not overly concerned about his latest flare-up.

“I was mainly just sore after my last bullpen,” Winn said. “I was a little surprised about getting the MRI, but I’m glad we did. It was kind of a precautionary thing to really make sure. It came back clean.”

With Winn likely to be sidelined for the start of Cactus League action, the Giants could take a look at a few of their other starting options early this spring, including No. 9 prospect Mason Black and non-roster invitees Spencer Howard and Daulton Jefferies. Sean Hjelle could also be a candidate to enter the mix, though Melvin has suggested that the 6-foot-11 right-hander might be better suited for more of a swingman role out of the bullpen.

Black, 24, logged a 3.71 ERA with 155 strikeouts over 123 2/3 innings in 29 starts between Double-A Richmond and Triple-A Sacramento in 2023, so he’s not far away and should have a chance to contribute to the rotation this year. Howard and Jeffries are among the few non-roster invitees with big league experience, though Jeffries is coming off Tommy John surgery and hasn’t pitched in the Majors since May 2022.

Howard drew praise Tuesday from general manager Pete Putila, who said the former top Phillies prospect is “throwing the ball really well.” Howard, 27, has recorded a 7.20 ERA over 38 appearances (29 starts) for the Phillies and Rangers, but he has a 3.66 ERA over his Minor League career and is feeling healthier than he’s been in recent years. He is out of options, so the Giants will make sure to closely evaluate him this spring.

“He’s going to get some opportunities,” Melvin said. “He might even get a start. Obviously, guys like that, we need to take a little bit harder look at.”

If Winn is unavailable to start the year, the Giants could make a bigger push to sign left-handers Blake Snell or Jordan Montgomery, both of whom remain available on the free-agent market. Snell has an offer on the table from the Yankees, though the Giants and Angels are still viewed as potential suitors for the reigning National League Cy Young Award winner, according to MLB.com’s Mark Feinsand.

Worth noting
Ace right-hander Logan Webb will start the Giants’ Cactus League opener against the Cubs on Saturday. First pitch is scheduled for 12:05 p.m. PT at Scottsdale Stadium (Watch live on MLB.TV).