Roki Sasaki’s Rise: The Dodgers’ Secret Weapon Shocking Baseball’s Biggest Stage

Everything he’s throwing — primarily his four-seam fastball around 100 mph and a splitter around 88 mph — is in the strike zone and missing bats. Out of 36 pitches, 26 have been strikes. Four of his five strikeouts have been on swinging strikes, and he’s generated 11 swing-and-misses in his four appearances.

For Sasaki, of course, the actual story isn’t just the end points. His first four pitches as a Dodger — against the Chicago Cubs in Tokyo to start the season — all topped 100 mph, but his elite velocity quickly disappeared and he struggled to get major-league batters to swing and miss, while also struggling with his control. Sasaki, who had 264 strikeouts and 49 walks in 202 innings in his final two seasons in Japan, had just 24 strikeouts and 22 walks in 34.1 innings through his May 9 start against Arizona, when he struck out zero of the 20 batters he faced.

A starter his first three years in the minors, the Anaheim Angels moved Rodriguez to the bullpen for the 2002 season, and he thrived, striking out 120 batters in 83.1 innings split between Double-A and Triple-A. The big-league club called him up in mid-September and he was dynamic, striking out 13 in 5.2 scoreless innings.

The Dodgers placed him on the injured list with a “shoulder impingement” and eventually sent him to Triple-A Oklahoma City for a rehab assignment that was as much about figuring out what was wrong as it was working his way back to full health.

In the World Series, he closed out three of St. Louis’ four wins, including the clinching Game 5, when Brandon Inge waved and missed at a curveball for strike three.

Called up to the bigs for the first time since May, Sasaki struck out four of the seven batters he faced over two scoreless relief outings. It was the first light the Dodgers had seen out of their bullpen all month, and given the state of the bullpen, it was enough for manager Dave Roberts to decide Sasaki was worthy of high-leverage situations in October. 

Simple, right?

The post Closing Time: Why Roki Sasaki is Thriving as the Dodgers’ Surprise Closer in the Postseason appeared first on Opta Analyst.

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His evolution into a shutdown reliever has been exactly what the Dodgers needed.
The bullpen, which was an unmitigated disaster heading into October, was the glaring flaw for a roster that was otherwise coming together and peaking at the right time. Highly paid relievers Tanner Scott and Blake Treinen have been so bad they can’t be trusted in any situation that matters. Kirby Yates’ ERA soared north of 5.00 before he landed on the IL in mid-September.

Francisco Rodriguez, Angels, 2002

Looking solely at the endpoints, this is exactly how the Los Angeles Dodgers saw this playing out: They signed the heralded and hyped Japanese pitcher Roki Sasaki in January 2025, and he’s become a playoff hero in October 2025.

Unlike Rodriguez, who would go on to a long career as an elite closer, Wainwright’s future in the big leagues was as an elite starter. But as a rookie in 2006, he became a reliable part of the St. Louis bullpen throughout the season, pitching mostly in the sixth, seventh or eighth inning.

The Angels leaned heavily on the youngster, and he responded. He made 11 playoff appearances — nine of them were scoreless and seven were more than one inning. In Game 2 of the World Series, he pitched three perfect innings, holding the line as his Angels rallied from a 9-8 deficit to beat the San Francisco Giants 11-10. In Game 7, Rodriguez — K-Rod, as he’d become known — struck out three Giants in a scoreless eighth inning, a day after pitching 2.2 innings in the Angels’ Game 6 victory.

Adam Wainwright, Cardinals, 2006

Except the Dodgers probably envisioned him on the mound for the first out, not the last one.

The righty with the big curveball was dominant in the postseason. He closed out all three of the Cardinals’ wins in the division series against the San Diego Padres and picked up a pair of saves against the mighty New York Mets in the NLCS. The curveball that froze Carlos Beltran with the bases loaded to end Game 7 — after St. Louis had scored twice in the top of the ninth to take a 3-1 lead — is an iconic moment for both the Cardinals and the Mets, in much different ways.

Jason Isringhausen had been the Cardinals’ closer since 2002 and had 33 saves in 2006 when a hip injury ended his season in early September. The Cardinals faded down the stretch, winning just nine of their final 23 games. Wainwright picked up the only two saves in that stretch, both in the last week of the season.

How does a young phenom, once destined to open games with a blazing fastball past 100 mph, find himself closing them out with surgical precision under postseason pressure? Roki Sasaki’s 2025 season with the Los Angeles Dodgers has been anything but a straightforward script. The Dodgers signed this celebrated Japanese star with visions of him setting the tone from the first pitch, yet here he is—rewriting the postseason record books as an unstoppable closer. Sweeping through innings with dominant strikeouts and nearly flawless control, Sasaki has become the bullpen savior the Dodgers desperately needed after a rocky regular season relief corps. What does it take to pivot so dramatically and thrive—or maybe it’s less about talent and more about grit and timing? Let’s dig into the journey that’s put Sasaki on the mound when the game’s final outs matter most, alongside the legacy of Dodgers greats and playoff heroes who paved the way.LEARN MORE

Roki Sasaki’s Journey Back

Sasaki spent more than a month in the minors, and, for most of that stretch, he just wasn’t very good. The 23-year-old right-hander who had become an instant legend in Japan at 19 didn’t even record the first strikeout of his Triple-A rehab assignment until he faced his 19th batter. As he muddled his way into September, Sasaki wasn’t a primary thought as the Dodgers mapped out their playoff pitching staff. He was an afterthought.

He’s doing things never before seen in baseball’s postseason. In Game 4 of the NLDS against the Philadelphia Phillies, for example, he became the first relief pitcher in major league history to string together perfect eighth, ninth and 10th innings in a series-clinching victory. So far this postseason, he’s pitched 5.1 scoreless innings of relief and has more saves (two) than combined hits/walks allowed (one).

We’ve seen similar stories in the past, of youngsters emerging in the bullpen to lead their teams on extended October runs. Here are two of the most prominent:

Most people assumed he wasn’t eligible for the playoff roster, though, because he hadn’t made his MLB debut until after the Aug. 31 deadline. But because he was on the club’s 40-man roster, the Angels were able to select him as an injury replacement and add him to the postseason roster. It was controversial at the time because that loophole hadn’t really been used and wasn’t general public knowledge.

If not for Sasaki, it’s hard to imagine the Dodgers still alive in their attempt to repeat as World Series champions.

Then, in a Sept. 9 start against Sacramento (no, not against the A’s), his velocity returned, and he struck out eight River Cats as he touched triple digits in the velocity category for the first time in months. Looking at the scenario in the big leagues — L.A.’s starting pitchers were getting healthy and the bullpen was imploding — the Dodgers moved Sasaki into a relief role. He struck out three while allowing just one walk in two appearances out of the bullpen.
To understand Roki Sasaki’s whirlwind season and new role as the Los Angeles Dodgers’ closer in the MLB postseason, you have to understand him, the franchise and pitchers who came before him.