Dodgers have a Roki Sasaki-sized problem

The Los Angeles Dodgers entered the 2025 season with two goals: to repeat as World Series champions and to develop Roki Sasaki at the major league level. 

So far, so good for the first goal. The Dodgers entered Saturday at 26-13, tied with the Detroit Tigers for the best record in the majors. As pitchers such as Clayton Kershaw, Blake Snell and Tyler Glasnow begin to work their way back from the injured list, the Dodgers will be much more formidable soon.

The same cannot be said for Sasaki's transition to the majors. Pitching on five days' rest for the first time this season, and with the roof open at Chase Field, Sasaki was walloped in the Dodgers' eventual 14-11 victory over the Arizona Diamondbacks Friday night. He allowed five runs on five hits, including a pair of home runs and two walks in four-plus innings, failing to strike out a batter. 

Sasaki had displayed signs of progress before Friday's outing. He had lasted at least five innings in his previous four starts, posting a 3.74 ERA and a 1.200 WHIP over 21.2 innings, striking out 15 batters with nine walks. Sasaki may not be dominating, but he got better each start.

Friday was a step back. He struggled from the outset, allowing two homers in the first inning. Sasaki's fastball was a problem again as he threw 36 fastballs without generating a whiff on 12 swings against. He averaged just 94.7 MPH with the fastball, his lowest velocity of the season.

While it is easy to point to the shorter rest for Sasaki's struggles vs. the D-backs, his fastball has been an ongoing issue. His 10.14% whiff rate on his four-seamer is the sixth worst of any starting pitcher to throw at least 100 fastballs. Bill Plunkett of the Orange County Register reported that Sasaki is unsure why his fastball is not up to expectations, saying through his interpreter that he and the Dodgers are "still in [the] process of finding out what the root cause" is.

Time is not on Sasaki's side. The Dodgers' pitching staff will return significant pieces in the rotation shortly. Meanwhile, Los Angeles will attempt to fend off the San Diego Padres and San Francisco Giants for the NL West crown. Unless Sasaki and the Dodgers figure out his fastball woes, a trek to the minors may be in his future.