GLENDALE, Ariz. -- All eyes were on the radar gun once Roki Sasaki fired his first Cactus League pitch on Tuesday night. The reading: 99.2 mph.

That first offering set the tone for a spring debut that did not disappoint.

"That's the best we've seen him," manager Dave Roberts said. "And you would expect that, given he's now really in compete mode, the adrenaline is real.

“We haven't seen 99 all spring."

Sasaki pitched three scoreless innings, striking out five while allowing one walk and a pair of hits in the Dodgers' 4-2 win over the Reds at Camelback Ranch. The 23-year-old right-hander followed Yoshinobu Yamamoto, who tossed four innings of two-run ball to open the game -- but Sasaki's next spring outing will likely be a start next Tuesday, Los Angeles' spring finale.

Yamamoto and Sasaki are expected to be the starting pitchers when the Dodgers and Cubs face off in the Tokyo Series from March 18-19, with Yamamoto starting the opener.

The Dodgers already had confidence in Sasaki's ability to pitch on a big stage, but it helped to see him rise to the occasion against Major League hitters -- even if it was only a spring game.

"Obviously, he's pitched in a lot of big games in his career," Roberts said, "but [that was] also in an environment where he's comfortable. This is something that's all new to him, and so he's learning on the fly. And we're asking a lot of him, but there's a lot of confidence supporting him."

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Here are the takeaways from Sasaki's Cactus League debut:

The radar gun
Sasaki's fastball velocity averaged 97 mph in 2024, down from 99 mph in '23. When he met with teams this past offseason, he gave them a homework assignment: figure out why his velocity dropped and develop a plan for fixing it going forward.

Tuesday marked the first time there was publicly available data on Sasaki's velocity. He fired his first pitch of the evening at 99.2 mph, a four-seamer that Noelvi Marte tapped to Mookie Betts at shortstop for the first out.

Sasaki averaged 98 mph on his four-seamer, 85.8 mph on his splitter and 83.3 mph on his slider.

"It was a combination of [adrenaline and improved mechanics]," Sasaki said through interpreter Will Ireton. "I really worked hard in the lab, dug into the mechanical aspect of my form and things I do well and things I wasn’t doing well."

The arsenal
Another big storyline surrounding Sasaki this spring has been whether his fastball-splitter combination is sufficient without another reliable pitch in the mix. Sasaki also throws a slider, but it's considered more of a work in progress.

True to form, Sasaki threw mostly four-seamers and splitters on Tuesday, with just three sliders mixed in. He threw 46 pitches, landing 26 for strikes, and got eight swing-and-misses from opposing hitters. Impressively, seven of those whiffs came on the splitter.

"A couple things that I noticed with big league hitters," Sasaki said, "they do hit mistakes and they do take some splits that I threw. But I did feel really good about being able to jam some hitters. As long as I am able to throw quality pitches, I should be able to get these guys out."

The reactions
Sasaki has thrown to his teammates and White Sox prospects in live batting practice, but this was the first time he really got to see how big league hitters reacted to his stuff.

Here's a collection of reactions from the Reds:

Outfielder TJ Friedl, who struck out looking in the fifth: "The splitter was like two different splitters from what I saw from my perspective. The first one he threw was hard, tumbling, kind of broke down and in. The 0-2 was more of a true splitter, kind of faded off. Then the last pitch he came back and kind of threw the other fork that came back into me. He’s got some good stuff.”

Catcher Austin Wynns, who notched the first hit against Sasaki in the fifth: "That’s pretty cool, but this is Spring Training. He’s going to give up hits. If he executes his pitches, he can miss with the execution because it’s so special, his stuff. If a pitcher is on and has his A-game, hitting his spots … you could tell he’s a little jacked up right there. He’s hyped up right now. I’ll take it. I’ll take it in the books. First hit.”

Manager Terry Francona: “It was impressive.”