Who is Will Klein? Meet the Dodgers reliever who played hero in that marathon World Series Game 3

Game 3 of the 2025 World Series will forever be remembered for Shohei Ohtani reaching base nine (!) times and Freddie Freeman ending the 18-inning marathon with a walk-off home run, but it wasn't just the stars who carried the Dodgers to a win and 2-1 series lead. Will Klein, the last reliever in the bullpen, threw four scoreless innings and picked up a well-earned W.

"Just keep going," Klein said after the game about his performance. "We weren't losing that game, and so I had to keep going back out there. I was going to keep doing that and doing all I could to put up a zero and sit back down and go do it again."

Klein had not thrown four innings in a game since he was in college and his 72 pitches far exceeded his previous season high (45 in Triple-A on Aug. 30) and his previous high as a professional (56 in Single-A on July 1, 2021). He held the Blue Jays to one single, two walks, and a hit batter in his four innings. The two walks came in Klein's fourth inning of work, when he was clearly out of gas.

"Will went four innings tonight, filled up the strike zone, competed his tail off," Dodgers manager Dave Roberts said after the game. "And in the postseason people talk about the superstars, but a lot of times it's these unsung heroes that you just can't expect, and guys come to pass and pop. Tonight was will Klein's night."

Klein is, literally, the last guy in the bullpen for the Dodgers this series. He was not on their Wild Card Series, NLDS, or NLCS rosters, and was only added to the World Series roster because the Blue Jays have a lineup that leans right-handed, which meant Klein made sense as a matchup option. Clearly though, he was not expected to pitch important innings, let alone four important innings.

So, who is Klein, the bullpen savior who set up Freeman for the walk-off home run and helped the Dodgers move to within two wins of their second straight World Series title? Here's what you need to know about the 25-year-old right-hander.

Four teams in 16 months

A fifth-round pick out of Eastern Illinois by the Royals in 2020, Klein has become well-traveled these last 16 months. Kansas City traded him to the Athletics in the Lucas Erceg deal at last summer's trade deadline. The A's designated him for assignment to clear a 40-man roster spot when they signed José Leclerc in January, then traded him to the Mariners for cash.

Klein never did get into a game with the Mariners, instead throwing 21 ⅓ innings with a 7.17 ERA for their Triple-A affiliate. They designated him for assignment in June to open a 40-man roster spot for top prospect Cole Young, who was called up to play second base. The Mariners traded Klein to the Dodgers for journeyman lefty Joe Jacques soon thereafter.

After spending most of his time with the Dodgers in Triple-A, Klein had a strong September cameo, throwing 15 ⅓ innings with a 2.35 ERA. He did walk too many batters though (10), which has long been an issue for him. Klein walked 36 batters in 44 Triple-A innings between the Mariners and Dodgers this year. Those walks are why he's on his fourth team in a little more than a year.

'Hitters do not get comfortable at-bats'

Klein was (and still is, really) a legitimate prospect, though not an especially well-regarded prospect because he is a reliever with walk issues, and those guys aren't exactly uncommon. Baseball America ranked him as the 18th-best prospect in the Royals' system before the trade last year. Here's a snippet of their scouting report:

Hitters do not get comfortable at-bats against Klein. He attacks with a double-plus fastball that sits 95-97 mph and touches 100 while playing up in the zone with vertical movement. His above-average 12-to-6 curveball is a hard downer at 82-84 mph that complements his fastball thanks to its hard drop, but he needs to land it more often for strikes down in the zone. Klein resumed throwing a high-80s slider/cutter that is now a plus pitch and a second swing-and-miss offering ... He lacks athleticism, and the stiffness of the body affects his ability to repeat his delivery, thus negatively impacting his control ... He can work himself into high-leverage situations if he continues to reduce his walk rate.

Klein hit 99.3 mph with his fastball in Game 3 and his final fastball -- his 71st pitch of the night -- clocked in at 96.8 mph. He was clearly running on fumes in that fourth inning, but even on fumes, Klein showed a plus fastball. Stuff is not an issue and never has been. If Klein throws strikes, something he did well in Game 3, he can dominate. We saw his upside in Game 3.

When will he be available again?

It's the World Series and everyone is available every night, though I have to assume Klein is an emergency-only option in Game 4 on Tuesday. He might be able to give the Dodgers an out or two (or three) in Game 5 on Wednesday. I'm sure the Dodgers would like to avoid Klein in Games 4 and 5, give him the off-day Thursday as well, then have him fully available on three day's rest in Game 6 on Friday if necessary. Given his workload and the series state, it's possible Klein has thrown his final pitch of 2025.

"Each time I went out and I felt my legs were tired I'm like, well, who cares?," Klein said after the game. "No one else is going to care that my legs are tired right now. The hitter doesn't care, so why should I? And just finding it in me to throw one more pitch, and then throw another one after that. And then sitting down and getting back up, the same thought going back out there for the next one. Like, putting up a 0, we're not losing this game. That's kind of what got me through it."