Lance Lynn Learned a New Trick

Since breaking into the big leagues back in 2011, Lance Lynn has featured one of the most fastball-heavy approaches in the majors. Now, that’s a little reductive, as he throws three different fastballs that he can ride, cut, or sink depending on what the situation calls for. Still, over 80% of the pitches he’s thrown in his career have been classified as a four-seamer, sinker, or cutter; that’s the third-highest rate of hard stuff thrown by a starter since his debut. And Lynn’s approach has only been amplified in recent seasons. In the last five years, over 85% of his pitches have been fastballs; no other pitcher has crossed the 80% mark.

When Lynn isn’t throwing a heater, he mixes in a curveball and a changeup, though neither pitch has been all that effective during his career. His four-seamer is a devastating pitch up in the zone, and his cutter and sinker allow him to work laterally to either side of the plate if needed. Utilizing all three of his fastballs effectively leaves little room for secondary offerings in his pitch mix. Why change an approach that’s worked for more than a decade?

Baseball is a game of constant adjustments, particularly in the context of the pitcher-batter duel at its center. In December, after announcing he’ll be pitching for Team USA in the World Baseball Classic, Lynn gave a fascinating quote about the adjustments he’s had to make in an interview with The Athletic’s James Fegan:

“People get so caught up in ‘Oh, you just throw fastballs.’ If you actually pay attention to the game, there’s speed differentials, there’s bigger breaks or smaller breaks. Part of evolving as a pitcher is giving the hitters different looks. Over time, you’re locking in the things that make you good, and you’ve got to figure out things that are maybe not as good as they can be. Over the last couple of years, Ethan [Katz] and I have been able to really concentrate on grips, different spin axes, and things of that nature that have really helped develop a pitch that comes out of a slot where it gives hitters difficulty.”

Despite relying on a fastball-heavy approach for much of his career, Lynn was faced with a number of circumstances in 2022 that forced him to evolve. The biggest hurdle was a knee injury he suffered during spring training that cost him the first two months of the season. Once he returned, he simply wasn’t his normal self; through the end of July, his ERA was a ghastly 6.42, though his FIP and xFIP were much better at 4.66 and 3.65, respectively.

The other difficulty he had to come to terms with was the deterioration of his fastball velocity. His four-seamer averaged 93 mph last year, its lowest average velocity since 2017, the year after his Tommy John surgery. As a 35-year-old, this eventuality was always looming, particularly for someone who relied so heavily on hard pitches. From a results standpoint, his fastballs were just as effective as ever, but the falling velocity portends the potential loss of effectiveness in the near future.

To combat this looming cliff, Lynn turned to a brand new breaking ball during the second half of the season. Here’s what his curveball looked like in his June 20 start, his second of the season:

That breaking ball’s shape is pretty vertical without much horizontal movement. Over the last few years, his curve has averaged under three inches of glove-side break. When located towards the bottom of the zone, it can be effective like we see above, but he’s used it more often as a change-of-pace pitch.

Beginning with his start on August 3, Lynn started throwing a completely new breaking ball. Here’s what that pitch looked like in September:

That’s a completely different shape. Pitch Info classified his new breaking ball as a slider, which is how Lynn referred to it in that December interview. Statcast classified that pitch as a curveball, but it’s clearly a different pitch than the one he was throwing earlier in the season. Whatever you call it, the pitch was a revelation. It averaged around eight inches of horizontal break while maintaining the same amount of depth and velocity as his old curveball. You can see just how different it was in his movement chart:

We only have a few months of data with this new slider, but it appeared to be more effective than his previous efforts at a breaking ball. His curveball had seen some success in the past, but it was far from consistent. Once he joined the White Sox in 2021, his usage of the pitch cratered to just 3%. Here’s how his new slider stacks up against his older breaking ball:

He managed to increase the whiff rate on his breaking ball while also reducing the amount of hard contact allowed. His usage of that new pitch peaked during his September 5 start against the Mariners. Lynn threw 20 sliders that day (more than 20% of his total pitches) and earned six swinging strikes with it. That was the most swings and misses he’s generated with a breaking ball since August 2019, when he collected seven with his curveball. (That was also the last time he had thrown a breaking ball more than 20% of the time.)

Adding the new breaking ball to his repertoire paid immediate dividends for his overall performance. From August 1 onwards, he posted a 2.43 ERA backed by a 3.27 FIP and a 3.31 xFIP across 12 starts. His 62 ERA- was ninth best in the majors during that time period, and his strikeout-to-walk ratio went from a good 4.9 to an elite 8.3.

What makes the introduction of this new slider all the more interesting is his goal of using it to keep left-handed batters at bay. When you think of a pitcher adding a pitch that breaks horizontally, it’s often used as a weapon against same-handed batters. For Lynn, this new pitch was a way to get a pitch under a left-handed batter’s hands in a way that his cutter just couldn’t. Here’s what that looks like in practice:

During his career, Lynn has run a pretty pronounced platoon split (nearly 50 points of wOBA). After adding the slider, his wOBA allowed against left-handed batters fell from .395 to .258, and his strikeout rate increased from 17% to 23%.

The introduction of this new pitch also had positive knock-on effects for his entire arsenal. Lynn set career highs in chase rate and swinging strike rate last year. Opposing batters also swung at his offerings more often than ever and made contact at a career-low rate. The moment he added the slider to his repertoire coincided with a significant jump in his chase rate and overall swinging strike rate:

Despite seeing significant improvement across all of his plate discipline metrics, his strikeout rate fell to 24.2%, the lowest it’s been since 2018. He did manage to reduce his walk rate to a minuscule 3.7%, which helped him produce the best strikeout-to-walk ratio of his career.

Should Lynn continue to hone and develop this new slider, he could be on the verge of a new chapter in his career. At 35, there were increasing concerns about his fastball-heavy approach. Instead of sticking with what had brought him so much success throughout his career, he took a step towards evolving his repertoire by giving batters a completely different look with a brand new pitch. The early results were promising. Now he’ll have to figure out how to fully incorporate the pitch into his arsenal to combat the inevitable decline of his fastball.