Yusei Kikuchi's impressive May showing gives Angels cause for celebration and concern

When the Angels signed Yusei Kikuchi to a three-year, $63 million deal, they were hoping to land an ace. After the first month of the season, what they got instead was an inconsistent performance that left something to be desired. Kikuchi finished April with a 4.31 ERA, however a strong May performance in which he's logged 28.1 innings with a stellar 1.91 ERA have pushed his season ERA all the way down to an ace-like 3.17, with a high point coming in his May 18 start against the mighty Dodgers where he held them to one run while avoiding an injury scare.

While the results, a sub-2 May ERA for example, indicate top of the rotation performance there's more than meets the eye as far as Kikuchi is concerned.

The Angels are celebrating Yusei Kikuchi's strong May, but they should be concerned if he can keep it up

For five-and-a-half seasons, Kikuchi was a middling starter with a 4.57 career ERA; however, a key adjustment he made following last year's deadline deal that sent him from the Toronto Blue Jays to the Houston Astros.

The Astros had him switch up his pitch mix, throwing more sliders and less curveballs while relying on high fastballs and an increase in changeups as well. The change in pitch utilization led him to record a dominant 2.70 ERA in 10 starts and 60 innings down the stretch in 2024, and it's an approach that he has brought to Anaheim this season.

On the surface, the results are there, with the one gripe being his failure to go deep into games as he's yet to surpass the six-inning mark in any of his 11 starts on the year. The underlying reasons for that lack of depth in games should be concerning to the Halos and indicate that the 33-year-old lefty still isn't the ace that was promised.

The primary reason that Kikuchi has had to leave the game after six or fewer innings has been his pitch counts, which have been driven up by his propensity to hand out the walk. On the season, his 11.8% walk rate ranks in the 18th percentile, and while in May it's been a bit better, he still ranks below average with a 9.9% mark.

The walks would be more acceptable if Kikuchi were missing more bats. His 8.15 K/9 on the season is the lowest mark since his rookie year in 2019, and in May, there has not been any significant uptick with an 8.26 mark that's barely better than the 8.04 he posted in April.

The high walk rate and lower-than-expected strikeout numbers are symptoms of what may be a grave problem. Kikuchi's not getting hitters to chase with a chase rate that ranks in the 19th percentile at 24.4% and a 21.7% whiff rate that's equally concerning, ranking in the 25th percentile.

Kikuchi does not have elite command and instead relies on the exceptional movement of his pitches, particularly his slider, to get chases out of the zone that result in swings and misses. He's not getting those this year, and even though his results in May have been stellar, this crucial aspect of his game hasn't been there.

As a result, there's been a lot of traffic on the bases, with a WHIP of 1.49 overall (1.60 in April and 1.38 in May), which he has been fortunate enough to wiggle out of more times than not.

Another constant in Kikuchi's career is his propensity to give up the long ball, which can be especially devastating with runners on. His career HR/9 sits at an alarmingly high 1.53, and that's with a much more average 1.06 mark in 2025 factored in.

That home run suppression might not stay so low, with his ground ball rate falling from a career mark of 43.7% to a below-average 37.9% rate in 2025.

At the end of the day, results matter, and if Kikuchi has truly developed the skill to escape jams and avoid the meltdowns that plagued him earlier in his career, perhaps he can keep delivering. However, the underlying metrics suggest that, even if he does that to an extent, his luck might run out, and his performance will suffer as a result.

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