Chicago Cubs: The Adbert Alzolay breakout is finally happening

In a season full of uncertainty for the Chicago Cubs, one thing has become clear and that is the team can count on Adbert Alzolay to be a part of the starting rotation for years to come.

It is nice to see that the Chicago Cubs might have finally developed their own pitcher.

After short stints with the big league club in 2019 and 2020, Alzolay looks like he’s locked himself into the Cubs’ starting rotation with a strong performance over his first six starts.

On the surface level, a 1-3 record and 4.50 ERA don’t scream breakout but diving a bit deeper shows that Alzolay’s actually made some big improvements to his game, largely through a change to his pitch mix.

In the limited innings Alzolay threw in 2020, he was predominantly a three-pitch pitcher. While his curveball was actually his most used pitch at a 33.1 percent usage rate, fastballs were really his bread and butter. He used his four-seamer 31.5 percent of the time and turned to his sinker for 20.7 percent of his offerings. He utilized his changeup and slider as well but those were used just 8.0 and 6.7 percent of the time, respectively.

This year, he’s flipped that script. Instead of being a fastball heavy pitcher, he’s started throwing his slider more than ever before at 46.3 percent of the time. He’s still throwing his fastballs pretty often, but the sinker and four-seamer (used at a 28.5 percent and 19.4 percent clip) have taken the backseat.

Interestingly enough, he’s also nearly abandoned his curveball. He’s thrown it just seven times so far in 2021 after using it more than any other offering last year. The shift in focus to his slider has paid off in a big way. The pitch is really really good and one of the best in baseball.

According to BaseballSavant’s Pitch Arsenal leaderboard, Alzolay’s slider is the 44th best pitch in the league in terms of run value with a -5 mark (in this case, negative is good). Looking at just sliders, Alzolay’s is the sixth-best in the majors.

Opposing batters are hitting .138 and slugging a measly .200 against Alzolay’s slider. They’re also swinging and missing a lot. Hitters are whiffing on 41.6 percent of their swings against his slider and striking out against the pitch 36.2 percent of the time. Take a look at this gif overlay of Alzolay’s fastball and slider:

Good luck hitting that.

Alzolay’s slider-first approach isn’t just getting great results with the one pitch either. It’s done wonders for his performance overall too. His swinging-strike rate and whiff rate have both seen big increases this year, currently sitting at 14.3 percent and 33.9 percent, respectively.

In addition to getting more swings and misses, Alzolay’s also demonstrated much better control this year. He’s cut his walk rate back significantly, dropping it nearly 10 whole percentage points from 14.9 percent to 5.7 percent. He’s done that by working in the zone more this year and getting ahead early in the count more often. His first-pitch strike percentage is up almost 11 points to 62.6 percent.

Alzolay’s improved control was clear during his last start in Cleveland. It was the first appearance of his career where he didn’t walk a single batter. That great showing impressed catcher Willson Contreras who had nice things to say about the Cubs’ up-and-coming starter after the game:

"He’s been making the adjustments he needs to make each start. Today, he showed me that he will be capable of going more than six innings. I talk to him a lot about not rushing with two strikes. Whenever he gets to two strikes, he gets so excited. He probably misses the location the most on two strikes. I think that the next step for him is maintaining the same rhythm that he has before two strikes and then try to execute on two strikes."

It’s been a rocky start to the 2021 season for the Cubs but Alzolay’s big improvement has been a bright spot. The Cubs’ starting rotation ranks second-to-last in MLB with a combined 5.18 ERA so his breakout couldn’t be coming at a better time.

With a Cubs team full of uncertainties, there’s one thing fans can know for sure and that is Alzolay is here to stay.