What is Wrong with Aaron Nola?

Aaron Nola has always been somewhat of an enigmatic pitcher. He is what we call an “ace.” Or at least, he is paid like it.

Nola just received a 7-year extension two offseasons ago. By annual average value (AAV), Nola ranks 15th among all pitchers, boasting an AAV of $24,571,429 per year. When considering total salary, Nola ranks 7th at $172,000,000.

In terms of monetary value, Nola is worth quite a bit. But when it comes to value on the field, it is difficult to justify such a high price tag.

Nola has never been a pitcher that wins with velocity. That is simply not his game. In 2024, his fastball, his best pitch by batting average, averaged 92.5 mph. In 2024, his best pitch by run value was his knuckle curve, which averaged 79.1 mph. When he’s on, he wins with precision and offspeed pitches outside the zone. When he’s off, he loses on the long ball.

In 2024, Nola tied for 5th in home runs allowed with 30. In 2023, he did not fair much better, allowing 32, which tied for 7th. This year, Nola has already given up four home runs, and he has only started four games.

Nola also tends to struggle the second time through a batting order. It’s become somewhat of a joke, as Phillies fans fear an Aaron Nola “Rav 4th Inning” (for the uninitiated, the Phillies’ 4th inning is sponsored by Toyota). But Nola does have an uncanny habit of spiraling at some point in the 4th or 5th inning of a game.

Still, despite his struggles with home runs, Nola typically grades out well and pitches nearly 200 innings, often playing deep into games, and giving the bullpen a much needed rest.

That has not been the case in 2025.

Nola may have only started four games, and he may have only pitched 20.1 innings, but the Phillies have an Aaron Nola problem. He is the 4th highest paid player on the team, but his performance has taken a drastic step backwards. His ERA sits at 6.65, well up from his 2024 number of 3.57. His WHIP (walks plus hits per inning pitched) jumped up to 1.66 from just 1.20 last season. His velocity is down across all five of his pitches, and the differences are concerning.

So what is wrong with Aaron Nola? Well, the unfortunate reality is that Aaron Nola is losing velocity, and his arm simply cannot afford to lose any strength. For a pitcher with such low velocity, even a tick off the speed gun is untenable. Batters are able to anticipate and react to his pitches, even more than they already could. If you’re searching for evidence, look no further than Nola’s 2025 barrel % and barrel/PA. Nola’s young 2025 season already well surpasses every other season of his career at 12.5% and 8.3, respectively. He’s throwing more balls, locating pitches poorly when in the zone, and getting behind in counts. That is not a recipe for success.

Perhaps Nola’s poor start to the season is a function of small sample size. Maybe he is hurt. Regardless, the Phillies’ strength this season was supposed to lie in their starting rotation. With Ranger Suarez injured, Taijuan Walker in the rotation and Nola underperforming, the Phillies strengths have become a weakness, a weakness that could keep the Phillies out of the playoffs. It’s only April, but there is something wrong with Aaron Nola, and right now, it does not seem fixable.

(All pitching analytics found from baseballsavant.com)

(All contract information found on spotrac.com)