This story was excerpted from Ian Browne’s Red Sox Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

ATLANTA -- Two seasons ago, Jarren Duran lost a fly ball in the twilight at Fenway Park for an inside-the-park grand slam by Raimel Tapia. Two weeks later, he lost multiple balls in the sun on a rough Sunday afternoon in Kansas City.

At the time, Duran’s confidence was completely shaken. Forget about trying to be an elite outfielder. Duran was just trying to survive as a Major Leaguer.

Last year, Duran made considerable improvements but was slightly above average as an outfielder at best.

And now? Duran is one of the best defensive outfielders in MLB. The metrics prove it. So too, does the eye test. Duran has been a standout defender in 2024.

Duran is at four outs above average this season, putting him in the 96th percentile. Last season, he finished at zero outs above average, putting him in the 57th percentile.

Defensive runs saved? Duran is at plus nine, the best of any outfielder. Last year, he finished with minus six.

As far as ultimate zone rating, Duran’s plus 2.1 ranks sixth among outfielders. Last season, he was at -1.7.

“That day in Kansas City, the Sun Bowl, it seems like that was 20 years ago,” said Red Sox manager Alex Cora.

Some of it is experience. Remember, Duran was an infielder at Long Beach State before the Red Sox converted him to the outfield when they drafted him in 2018.

However, much of it is the hard work he does behind the scenes with Red Sox outfield coach Kyle Hudson.

“We worked a lot in spring on his glove, and the main focus was being able to finish plays, because he was getting to balls and he just didn’t finish the plays last year,” Hudson said. “Just that focus on the glove has built his confidence to get to the ball, and for him to understand that if he gets to it, he has the ability to complete the play.”

Though Duran has always been known for his blazing speed, he has maximized his steps this year by changing his running form. That has helped at the plate, as Duran leads MLB with six triples. It has helped on the bases, as Duran is tied for third in the American League with nine stolen bases. And it has also helped in the field.

“I mean, with his running form and his gait, that was a big part of the outfield development too,” said Hudson. “Just kind of getting him more in line and the fundamentals of his running gait to be just a little bit less violent so that he's less all over the place.”

When the season started, Duran was expected to settle mostly in left field with brilliant rookie defender Ceddanne Rafaela stationed in center. But a couple of weeks after Trevor Story suffered a season-ending left shoulder injury, the Red Sox moved Rafaela to shortstop to stabilize the infield.

That led to Duran going back to center. And he is now playing that position like he owns it.

Another subtle improvement Duran has made is with his throwing arm. These days, when he comes up firing, he looks much more like an outfielder than the second baseman he once was.

“He's making smart decisions on where to throw the baseball,” said Hudson. “And his arm has come a long way in comparison to even last year. And he's continued to build on that and we’re reaping the benefits of that. He’s holding guys from taking that extra 90 feet, where maybe in the past, they would have.”

And perhaps most importantly for a team that has been ravaged by injures this season, Duran has posted every day. He is the only Boston player who has started the first 37 games of the season.

“He’s out there working every single day and it's actually been a conversation, we want to dial back some of the stuff that we do on the defensive side [before the game] just because he is in the lineup every single day and he is running around center field every single day,” Hudson said. “So we need to kind of manipulate his work and the amount of his work and limit some time on his feet. I’ve talked to all outfielders I've had in the past and I always I always tell them, ‘You want to lead the league in innings played.’ And he's doing it.”