BOSTON -- For all the uncertainty that surrounds the 2020 baseball season, the Red Sox are now faced with one grim certainty.

Chris Sale won’t throw a pitch this season.

After the team announced on March 19 that its ace lefty will undergo Tommy John surgery, Sale's procedure was announced on Monday to have been a success.

“Needless to say, this is a tough, tough thing for Chris and tough for all of us here with the Red Sox,” said Red Sox chief baseball officer Chaim Bloom. “Chris is an outstanding pitcher, and although I haven't known him very long, I'll tell you, in the time I've spent with him, you will not find a more straightforward, more accountable person than him in this game.

“While we are bummed for him, we know he's going to attack his rehab like he has everything else in his career. We have confidence that he's going to do well coming out of this.”

Judging by previous timetables for starting pitchers who have had Tommy John surgery, a best-case scenario could have Sale pitching for the Red Sox in June or July of 2021.

“It obviously varies,” said Bloom. “I think generally 12 months would be pretty aggressive [to return]. Usually it takes longer than that to make sure you’re doing the build-up properly. I think often we see 14 to 15 as kind of that mid-range. But everybody is different.

“The one great thing with Chris is so much of how these rehabs go is based on what the player puts into it. You know with him, he’s going to put everything he can into this and get himself every chance to not just come back quickly but come back successfully.”

There had been a sense that it could come to this. On March 5, the Red Sox and Sale announced that the pitcher had a strained flexor tendon.

However, Sale seemed to be bracing himself at the time that surgery was possible -- if not inevitable -- if his elbow didn’t respond after what turned out to be a rest period of about 10 days.

“I think because of the way this unfolded, it didn't come out of nowhere,” said Bloom. “We knew when it got to that point, this was possible.”

Sale did some light throwing in the batting cage at JetBlue Park on Friday and Sunday before the team's announcement. He played catch Tuesday on flat-ground, and that’s when the pivotal red flag occurred.

“He experienced enough pain that we had to put a stop to it,” Bloom said. “He huddled with us, from folks that were on site and on the phone, where we put our heads together and made this determination. We knew obviously when he had the setback at the beginning of the month that this was a possibility. When we let the flexor calm down and ramped him up again, he didn't respond as we had hoped and that's where we are today.”

The MLB season was supposed to start on March 26, but it has been delayed due to the coronavirus pandemic.

That also provided logistical challenges to figuring out when and where Sale will have surgery.

“Obviously it’s something we’re mindful of, No. 1, the difficulty generally surrounding elective surgeries with what our country is going through and also making sure that we’re doing this in a way that doesn’t put any extra burden on the public health system,” Bloom said. “Those are definitely considerations as we work to get this set up and get this done. We’re going to make sure that we do it in a way that doesn’t place any undue burden on everybody who is suffering as a result of the outbreak.”

When the Red Sox start up again, their rotation will have Eduardo Rodriguez, Nathan Eovaldi and Martín Pérez, followed by uncertainty in the final two spots. Ryan Weber is the front-runner for the No. 4 spot after giving up no runs in three Grapefruit League outings.

Before Spring Training was shut down last week, Red Sox interim manager Ron Roenicke appeared to be leaning toward using an opener in the No. 5 spot.

The loss of Sale is crushing to the Red Sox, who traded Mookie Betts and David Price to the Dodgers just before Spring Training started.

This season is the first of a five-year, $145 million contract that Sale signed a year ago.

Now that Boston knows Sale will be out for the season, Bloom might ratchet up his quest to acquire another starting pitcher when MLB returns. But any move will be made with the big picture in mind.

“Of course we want to do everything we can to compete this season, and we still have that outlook,” said Bloom. “But we need to make sure that we’re viewing the big picture as well. What that’s going to mean as we go forward, it’s hard to say anything specific, but needless to say, losing Chris for 2020 is not going to make our task any easier.

“It is going to create some opportunities for some guys to step up and you never know what’s going to happen with that, especially with the added uncertainty that surrounds this season generally, but it’s not going to make this any easier.”

Boston brought in righty swingman Collin McHugh two weeks ago, but his timetable is uncertain as he rebounds from a strained flexor tendon that he dealt with last season.

In December 2016, the Red Sox acquired Sale from the White Sox as part of a blockbuster deal that sent infielder Yoán Moncada and flame-throwing righty Michael Kopech to Chicago.

Nobody can dispute how beneficial the Sale trade was for the Red Sox in his first two seasons.

In 2017, Sale was dominant, going 17-8 with a 2.90 ERA while leading MLB with 308 strikeouts.

Though he worked through some shoulder problems in Boston’s World Series-championship winning season of 2018 and a mysterious stomach ailment during the postseason, Sale was magnificent when he pitched, going 12-4 with a 2.11 ERA and 237 K’s in 158 innings.

It was Sale who threw the lethal slider to strike out Manny Machado to end the decisive Game 5 of the 2018 World Series at Dodger Stadium.

Christian Vázquez jumped into Sale’s arms in a moment of euphoria for the Red Sox.

However, little has gone right from a baseball standpoint for Sale since that moment. Last season was the toughest of Sale’s career, as he went 6-11 with a 4.40 ERA in 25 starts before he was shut down with the elbow issue.

“For sure, over the last year and up to this point, I’ve done nothing but fall flat on my face,” Sale said on March 5. “So that’s a gut punch and a tough realization. But I’ve said time and time again, I have no time to hang my head and sit in the corner and pout. I’ve got work to do and I’ve got an uphill battle to climb, but I’ve got my climbing shoes on. So, I’ll be ready to roll whatever way we’ve got to go.”

Sale now knows which way that is. And though it surely represents the longer road back, Sale hopes to rediscover his dominance once he returns.