Twenty-one games into the season, it might be too early to name an unsung hero of this Red Sox season. But if there is one, it’s righty Josh Winckowski.

On a night Nick Pivetta threw 5 ⅔ solid innings, Alex Verdugo homered again and Kenley Jansen posted yet another easy save, Winckowski may have been the most important part of Boston’s 5-3 series-opening win over the Brewers. Pitching in relief of Pivetta, the righty struck out four batters in 2 ⅓ scoreless innings as his ERA dropped to 1.65 on the season. With the Red Sox operating with a six-man rotation, they are one man short in the bullpen. Having someone come in and dominate like Winckowski has so far has made life easier on manager Alex Cora.

“(Winckowski) has been outstanding,” Cora said. “We can talk all we want about Dugie and whatever, but this kid, Winc, he put the work in the offseason. He cleaned up a lot of stuff physically, mechanically, mentally. We’re very pleased with the way he’s throwing the ball.”

Winckowski’s up-and-down rookie year as a starter ended poorly as he struggled down the stretch and finished with a 5.89 ERA in 70 ⅓ innings. Entering 2023, he found himself pretty far down the club’s rotation depth chart and was not expected to make the club out of spring training. A strong camp and a series of rotation injuries put Winckowski in the mix for a long relief role. So far, he has savored the opportunity.

Winckowski has already appeared in eight games for the Red Sox, logging 16⅓ innings in the first three weeks of the season. He has allowed just three earned runs and 11 hits while striking out 15 batters. Quietly, he has aptly served a bridge relief role similar to Garrett Whitlock’s dominant multi-inning part in 2021.

On Friday, Winckowski got a quick third out in the sixth inning after Pivetta issued a two-out walk to Brian Anderson with the Red Sox clinging to a 5-3 lead. He tossed a 1-2-3 seventh, then escaped trouble in the eighth by striking out Anderson with runners on the corners and two outs. Winckowski was demonstrative as he came off the mound, screaming and pumping his arms. He bridged the gap to the closer, Jansen, who continued his dominant start to the season with a 1-2-3 ninth.

“Winc did a tremendous job,” Pivetta said. “Kenley closing it down. All in all, a good game.”

Over the winter, the Red Sox made a significant investment in their bullpen, signing Jansen and setup man Chris Martin to multi-year deals while also giving Joely Rodríguez a multi-year contract and obtaining Richard Bleier in a trade for Matt Barnes. The fact that both Winckowski and Kutter Crawford, who allowed one hit in 6 ⅓ scoreless innings as a reliever Monday, have emerged as multi-inning weapons is something of a bonus in a group that is much-improved from last year.

As the Red Sox finish off a stretch of 19 games in 19 days with a six-game road trip to Milwaukee and Baltimore, the fact Winckowski was able to save the bullpen with a pristine performance Friday was meaningful.

“He came in and did his job,” Cora said. “That’s what we’re going to do with Winc and Kutter. When we use them, go multiple innings.”