The Los Angeles Dodgers’ prized pitcher came with 100 mph heat and superstar hype. But so far, Roki Sasaki‘s fastball is getting hit more than hyped.
When the Dodgers signed Sasaki out of Japan, the expectation was dominance. Triple-digit velocity. Unhittable splitters. A front-line ace to replace what they lost with Shohei Ohtani’s injury.
But now, seven starts into his MLB career, Sasaki’s biggest pitch is his biggest problem.
Velocity Without Results
Sasaki’s four-seam fastball, which once hit 100.6 mph in the Tokyo Series, is one of the least effective heaters in baseball by whiff rate. According to CBS Sports’ Mike Axisa, among pitchers who have thrown at least 200 four-seamers, Sasaki ranks second-to-last in swing-and-miss rate at 11.0%—nearly half the league average (21.3%).
Only Rockies starter Antonio Senzatela has a worse whiff rate on the pitch.
Even more surprising? Opponents are batting .232 with a .406 slugging percentage against Sasaki’s fastball—numbers that are league average for most, but a major disappointment for a guy throwing 97-98 mph consistently.
Pitch Shape Over Stuff
So why is the fastball failing? It’s not the radar gun. It’s the lack of movement.
Dodgers pitching coach Mark Prior told The Athletic that Sasaki is intentionally reducing his velocity in an attempt to gain better command. “He’s not throwing 100 with us,” Prior said. “He felt like it affected his command tremendously.”
But Axisa points to the real issue: poor pitch shape. Despite the velocity, Sasaki’s fastball doesn’t have the vertical rise or deception necessary to beat MLB hitters. It’s flat. It’s trackable. And right now, it’s not missing bats.
Dodgers Don’t Seem Panicked—Yet
Prior said the Dodgers are “in bed with where we’re at” regarding Sasaki’s fastball mechanics, meaning they don’t plan to overhaul anything midseason. That makes sense—Sasaki signed in late January and had just a few weeks to ramp up before the Dodgers’ Tokyo Series debut.
Still, L.A. is clearly betting that time and offseason development will fix the issue. Sasaki’s slider and splitter have shown flashes of dominance, and he owns a 3.86 ERA despite the struggles.
Early Days, But Expectations Are Sky-High
Sasaki is only 23, and it’s worth remembering he didn’t get a traditional spring training or gradual entry into the majors. But with an $8 million investment (including a $7.26M signing bonus), the Dodgers didn’t bring him in to be average.
They brought him in to dominate. And right now, that dominance has been missing—especially with his supposed best pitch.
Can They Unlock It?
The Dodgers have a reputation for developing elite arms. But can they turn Sasaki’s velocity into a true weapon, or will his fastball remain a flaw that opponents exploit?
Sasaki’s development also carries added pressure given the spotlight he’s under—not just from fans in Los Angeles, but from baseball fans in Japan who followed his every pitch with Chiba Lotte. He’s not just pitching for the Dodgers; he’s carrying international expectations, and any struggles are magnified in both markets.
The talent is undeniable. But if Sasaki’s going to evolve into the ace he was projected to be, it starts with making that heater more than just a number on a radar gun.
Dodgers’ $8 Million Arm Has a Fastball Problem