MILWAUKEE — If the Brewers are to extend their surprise season deep into October, they’ll have to do it without their All-Star left fielder. Christian Yelich will undergo season-ending back surgery on Friday, he announced in a video message on Thursday evening.

The development comes after Yelich spent the last three weeks undergoing treatment in a desperate effort to return later this year to help the Brewers in their bid for a fourth division title in the seven seasons since his arrival in Milwaukee.

“It just got to the point where it wasn’t getting better,” Yelich said. “I tried everything I could. I ran out of options and it came time to make a decision.”

Surgery, he explained, “was the best option that we had left. It sucks. There’s really no other way to put it other than it sucks. It’s terrible. But it’s part of sports. These things happen. You get hurt, you get fixed and you get back out there.”

Yelich, 32, will undergo the procedure in Milwaukee and said in an accompanying statement released by the Brewers that he expects to be “back at 100 percent for next season.”

The injury ended Yelich’s best season since 2018-19, when he won back-to-back NL batting titles and finished in the top two of NL MVP Award balloting, winning the honor in ’18. This season, he posted a .315/.406/.504 slash line in 73 games and was the top vote-getter among NL outfielders in All-Star Game balloting.

But when Yelich started in right field for the NL at Globe Life Park on July 16, he was already managing renewed discomfort in his lower back, which has been problematic dating back a decade to his days with the Marlins. He missed 22 games in April and May of this season with a low back strain before returning to action and surging to the Midsummer Classic.

On July 24, in a 1-for-19 funk over his last six games and unable to continue managing the flare, Yelich succumbed to another IL stint. Now, he’s succumbed to surgery.

“You try to stay as positive as possible about it,” said Yelich. “It’s going to be for the best. Short term, terrible. Long term, it’s going to be all right.”

He made clear in his statement that he intends to stay with the team, which has been relying on rookie Jackson Chourio in left field most days. Chourio hit his 15th home run of the season in the first inning of Thursday’s series finale against the Dodgers and needs five more home runs and four stolen bases in his bid for a 20/20 season as a 20-year-old.

Yelich will support Chourio and the rest of Milwaukee’s young roster as best as he can.

“It’s so weird when you’re hurt,” he said. “You feel like you’re on the team but you’re not. You’re kind of just there. You help out in any way you can, but you’re not really in the grind with the guys really to have any impact on what’s happening out there.

“But it’s a great group of guys, and they’re playing extremely well. I’m happy to watch them and see what they’re going to do. Hopefully they can win the division, get into the playoffs, and then once you’re in the postseason, it’s like, who knows what’s going to happen? You get hot and it could be a cool run. I’m excited for them.”