How Corey Kluber can optimize his arsenal

Collin McHugh’s adjustments can point us in the right direction.

Just before the MLB lockout froze all transactions in December of last year, the Rays officially signed Corey Kluber to a one-year deal for the upcoming season.

The 35-year old right hander is coming off of a productive season in Yankee pinstripes as he posted a 3.83 ERA and a 3.85 FIP across 80 innings. Unfortunately, he missed the final three months of 2021 with a right shoulder strain, but all indications are that he is fully healthy to begin this season. Kluber threw 50 pitches in his first Rays spring training start this past Saturday.

Beyond just his surface level stats, there are also other reasons to believe that Kluber is still an effective pitcher despite his age. In 2021 he posted an above-average Whiff%, HardHit%, and Chase rate which all speak to the well-rounded skillset of the veteran hurler. Kluber doesn’t need to change a thing to produce at a high level in 2022 as long as the quality of his stuff doesn’t take an unexpected downward turn.

This is the Rays we’re talking about though, a team that is always tinkering with in-game strategies, and especially so with their pitching staff. It’s logical to assume that the team will make suggestions to help Kluber optimize his arsenal, so let’s take a stab at identifying what they might be.

The Pros and Cons of Kluber’s Pitch Mix

Kluber has leaned on a five pitch mix for the majority of his career and he stuck with that attack plan in 2021. His offerings were distributed pretty well as he threw 29% curveballs, 27% cutters, 25% sinkers, 14% changeups, and 5% four-seamers last season, per baseball savant.

You’ll notice he leans the heaviest on his curveball, and that is for good reason. Kluber’s curveball has been his bread and butter ever since he entered the league, and it still ranked among the top curveballs in Whiff% last year. Batters also hit just .186 with a .289 SLG against the pitch in 2021.

Here’s what that glorious curveball looks like in Tropicana Field:

As seen in that clip, the pitch gets great horizontal movement which is a large part of why it has induced a wealth of whiffs and weak contact during the entirety of Kluber’s career.

If we take a look at Kluber’s curveball in context with the rest of his arsenal, it stands out in that regard too. The table below lays out various results metrics for each of his five pitches during the 2021 season:

While the success of his curveball definitely stands out, another takeaway here is that his fastballs were hit awfully hard.

Some of that can probably be attributed to the fact that both Kluber’s sinker and his 4-seamer averaged below 91 miles per hour for the first time in his career last year. That trend probably won’t be reversing itself as Kluber continues further into his mid-30’s.

Last season, Corey Kluber gave up 76 hard-hit balls (95+ mph exit velocity) in total. Almost half of all of those batted balls came off of fastballs, despite Kluber only throwing heaters about 30% of the time. Here’s a breakdown of which of his pitches resulted in hard hit balls most often last year:

So, how is the new Rays starter going to continue to succeed despite his diminishing arm strength and poor fastball results? The answer may actually lie within the adjustments that one Rays pitcher made just last season. That pitcher is Collin McHugh.

The similarities between Corey Kluber and Collin McHugh

Collin McHugh is no spring chicken himself, as he’ll be turning 35 this coming June. Like Kluber, McHugh also has seen his fastball velocity decline with age, but that didn’t stop Collin from turning in a career year out of the Tampa Bay bullpen.

The Rays gave McHugh a very specific attack plan last season and because of the similarities between both pitchers, Corey Kluber may follow in his footsteps in 2022.

Let’s start with both pitchers’ biggest strength, their breaking balls. While McHugh’s breaker is technically classified as a slider and Kluber’s is labeled as a curveball (per Baseball Savant), that differentiation is a moot point because of how similar the two pitches are.

Both benders are thrown at similar speeds, with McHugh’s slider averaging 79.3 mph in 2021 and Kluber’s curve sitting at 81.9 mph, a gap less than 3 mph.

In addition to velocity, both breaking balls are near spitting images of each other with regards to movement. The graph below plots the average horizontal and vertical movement of all sliders and curveballs thrown at least 30 times during the 2021 season:

These two breaking balls mirror each other very closely, but the similarities between both pitchers don’t stop there.

McHugh’s other main pitch in 2021 was his cutter, a pitch that Kluber also leaned on. Their cutters actually averaged an identical 87.6 mph during the 2021 season. The difference in spin rate between the two cutters was less than 50 RPM and the two pitches move in a very similar fashion as well. The graph below shows the average movement of all 2021 MLB pitchers’ cutters (minimum 30 thrown):

Kluber and McHugh have similar pitch repertoires, and it’s no coincidence that the Rays targeted both of them in free agency.

Side note: If you want to take the comparisons up a notch further, go check out new Rays free agent signee Brooks Raley’s cutter and breaking ball movement. His pitches move in nearly the exact same way that McHugh and Kluber’s do. You could say the Rays have a type.

The similarities between the two pitchers extend to their fastballs, too. Both pitchers have seen their fastballs induce much poorer results than their breaking balls have over the course of their careers.

Just like Kluber, McHugh lives in the low 90’s with his heater and has also tinkered with both a sinker and a 4-seam in various seasons. The fastball spin rates of both veterans sit in the 2100-2200 rpm range as well.

The reason why these two have such similar arsenals is in large part due to their release points. This checks out from both a metric (their release point measurements are very similar) and a visual perspective. Here’s a still image of both of their releases:

McHugh’s slot is slightly lower than Kluber’s, but they both use the same low three-quarters release.

There’s no need to keep beating a dead horse, these two pitchers are extremely alike in many ways. Given this, doesn’t it make sense for the Rays to try to make some of the same tweaks with Kluber as they did with McHugh last year?

Collin McHugh’s adjustments with the Rays

Over the course of his career, McHugh has experimented with a number of different pitches and has done so in a number of different roles. He was able to take his game to a new level last year and that directly coincided with a pitch mix change:

McHugh’s pitch percentages in 2021 look drastically different than any other year of his career.

First, his fastball usage across the board ticked way down. McHugh completely scrapped his sinker and also threw the lowest percentage of 4-seams in his career. McHugh essentially used his cutter as his main “fastball”, as he threw that pitch much more often compared to his previous four seasons. It’s also worth noting that Collin really trusted his cutter against lefties, as he used it 45.1% of the time to them.

The other notable takeaway here is that McHugh’s slider usage skyrocketed in 2021. That slider was likely a huge reason as to why the Rays targeted McHugh in free agency, and he sure did throw it a ton (53%) over the course of the season. Righties, lefties, it didn’t matter. McHugh was throwing that sweeper to everybody and in almost every count.

The Rays essentially simplified McHugh’s pitch mix by minimizing his weakest pitches (sinkers and 4-seams) and maximizing his strongest pitches (cutters and sliders). Having a plethora of pitches is great, but if a few of them don’t generate good results, it’s probably best to tuck those away (and especially so if the arsenal contains other pitches that are very good). That brings us to Corey Kluber.

The adjustments Corey Kluber should make with the Rays

Given the similarities between these two, it’s logical to think that the Rays may want Kluber to use his pitch mix in the same way that McHugh did. For comparison’s sake, McHugh used his breaking ball a whopping 53% of the time last year while Kluber’s was at just 29%. Kluber has started to throw that pitch a bit more recently though, his usage of it in 2021 was actually a career high.

Should Kluber throw his great curve as often as McHugh did last year? No, probably not that much as there are more factors in play here. For one, Kluber will be asked to go through opposing lineups multiple times which differs from McHugh’s shorter stints. Another potential question is whether throwing more curveballs would also lead to more batters walked for Kluber?

These are valid questions to ask, but because of how great that curve is, it’s probably worth trying to find some answers. Instead of a 29% curveball usage, could Kluber get that number up over the 35% mark? What about up and into the 40% range? The Rays seem likely to explore this, and if it doesn’t work out, he can always revert to his old patterns, which are plenty effective.

When the usage of one pitch comes up, a different pitch’s usage must come down. For Kluber that should probably be his sinker, which has consistently performed worse than any of his other pitches. It probably won’t hurt Kluber to throw occasional sinkers to righties at times (plus the Rays love to throw sinkers to same-sided hitters), but the overall 25% sinker usage is probably too high.

It’s worth noting that Kluber’s sinker usage last year in New York was actually a career low for him, so there’s some evidence that he is already trending in the direction that the Rays will likely push him even further in.

The Rays may also suggest that Kluber should use his cutter instead of his sinker in situations where he is wanting to go that pitch. That’s essentially what McHugh did last year (way more cutters, way less fastballs) and given how similar both cutters are it makes sense for Kluber to give it a whirl as well.

Replacing a good chunk of those sinkers with more curveballs and cutters seems like the best avenue for Kluber’s improvement moving forward. This shift in pitch mix already worked wonders for one aging Rays pitcher, why not run it back for round two?