LAKELAND, Fla. -- The Yankees got some more concerning news on the injury front on Friday, when manager Aaron Boone confirmed that center fielder Harrison Bader, who was taken out of Wednesday's game with a strained left oblique, is likely to be out for Opening Day on March 30.

"I don't have a time frame for you yet, because the doctors are weighing in on it today," Boone said. "It'll be some time."

Though he didn't commit to a timetable, Boone estimated the normal recovery time for this type of injury to be four to six weeks.

"He's got a great mindset -- do all I need to do to get back," Boone said. "He's in a really good frame of mind. That's just who he is."

Bader's injury further complicates the Yankees' outfield situation, which is far from settled. Boone mentioned Oswaldo Cabrera, Estevan Florial, Rafael Ortega and Aaron Hicks as players who will get a look in center field for Spring Training, and Aaron Judge has not been ruled out of playing that position on Opening Day.

"Could be," Boone said. "Depending on how long [Bader's absence] is, and maybe not even on how long it is."

Florial started Friday's game in center field with Ortega in right and Hicks in left.

Bader's setback comes halfway through a spring in which New York's pitching staff has also been hammered by injuries.

Four Yankees pitchers, including two prospective starters, are likely to start the season on the injured list. Carlos Rodón, who signed a six-year contract in December, has a strained forearm and Frankie Montas had shoulder surgery in February. Relievers Lou Trivino (elbow ligament strain) and Tommy Kahnle (bicep tendinitis) are also sidelined.

Severino stretches out

Luis Severino, one of New York's healthy veteran starters, delivered a welcome silver lining for the injury-riddled Yankees on Friday. The right-hander pitched four innings in Friday's 4-3 win over the Tigers, with three strikeouts, four hits and two earned runs. Except for giving up a couple of solo shots, Severino pronounced his day a success.

"Of course I want to go out there and throw shutout innings, but the main thing for me is being healthy," Severino said. "Actually when I finished today I thought it was the third inning. I feel healthy out there, and hopefully next time I'll go farther."

The recent rash of injuries, especially to pitchers, would seem to justify the Yankees' decision to be cautious with Severino's workload, especially in not allowing him to pitch for the Dominican Republic in the World Baseball Classic. The 29-year-old has had some problems keeping the ball in the yard in his first three starts this year (five home runs in 8 2/3 innings), but at least he is building up his pitch count.

"I wouldn't say I'm happy about [the Yankees' decision] but I won't say I'm against what they wanted me to do, because at the end of the day, my purpose here is to be healthy all year and help us win the World Series," Severino said. "They've told me that the competition there is like being in the playoffs. If you lose two games, I think you're out. So everybody's giving 100 percent. I understand why they don't want me pitching at that level right now."

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Boone also offered his perspective on the matter.

"There's no perfect time to have the WBC," said Boone. "But I think with some pitchers, it always gives you some pause that they're going to amp up and you're going to get in these games where a lot's on the line, and you're pitching October-like games while you're still building up for the regular season."

Since 2018, when he won 19 games and finished in the top 10 in American League Cy Young Award voting for a second straight year, Severino has started only 26 games because of Tommy John surgery, COVID-19 and other injuries. Nineteen of those starts came last season, which he finished strong and healthy.

So giving up some wind-blown home runs in Spring Training is not going to bother Severino, as long as he is pitching in the first round of the rotation.

"My slider sucks, that's what [hitters are] telling me right now," Severino said. "It's nothing more than just location. The fastball to [Kerry] Carpenter was a good pitch -- a fastball inside. That's what I was trying to throw. Credit to him [for hitting it for a homer]."