Kimbrel is Better than Ever

I really hate (love) when I am right about something regarding baseball and especially the Chicago Cubs. As soon as the Cubs signed Craig Kimbrel in the 2019 season, I was excited! Kimbrel is a future Hall of Fame closer and the Cubs needed someone desperately. But… the results really weren’t there in that season, posting a 6.53 ERA in 23 appearances. What really hurt was late in September, Kimbrel blowing a save against the St. Louis Cardinals which essentially sank their season. But fast-forward to the 2021 season and Kimbrel is better than ever.

The 2020 season didn’t start out great either. In first four games, Kimbrel had a 23.63 ERA, 12.06 xFIP, and was walking 16.88 batters per nine innings. With Jeremy Jeffries waiting in the wings, Cubs fans began calling for him in the ninth over Kimbrel.

But after that start through the end of the 2020 season, Kimbrel started putting it together. He posted an 1.42 ERA, 2.05 xFIP, and was striking out hitters at an alarming rate, earning an 18.47 K/9. Kimbrel has brought that success into the 2021 season and has become one of the most dominant pitchers in the game again.

But what was the change that turned this around? The first thing we can see is his pitch velocity. In the first four games of 2020, Kimbrel averaged 96.4 MPH on his fastball. This, while still fast, was a hittable pitch compared to a lot of the fastballs in the league. Essentially, without an elite FB, Kimbrel was predictable and hittable. From August 14th through the end of the season, Kimbrel averaged 97.3 MPH on his fastball and was getting 7.3 inches of vertical movement.

Looking at the 2021 season, Kimbrel has held that 97.3 MPH avg fastball and he is getting 7.5 inches of vertical movement. In the 2019 season, by far Kimbrel’s worst season as a pro, he averaged 96.2 MPH on the fastball. An 1.1 MPH difference in his fastball shouldn’t be the difference between a 0.66 ERA and a 6.53, but from a velocity and movement perspective, there aren’t any other alarming differences. So, what was the big change?

The big buzzword in the industry is “spin rate” and possible sticky substances. The reason spin is important is it simply makes the pitch better. A curveball thrown with a lot of spin will cause the ball to move more. A fastball thrown with a lot of spin will allow it to move more and almost defies gravity. If you’ve heard of a “rising fastball” it is really just a fastball thrown with a lot of spin, which causes gravity to have a less dramatic effect on the ball. So has Kimbrel added spin which has also added velo or allowed his fastball to be considered elite again?

No.

In the 2019 season, Kimbrel had an average spin of 2,323 revolutions. In 2020, he actually dropped a bit to 2,266 and in 2021 he increased it back up to 2,325. So really, that’s not the difference here either. The difference is a mechanical change that has cleaned up the movement on the fastball.

What was the change?

The change is very minuscule and difficult to see with the naked eye. On delivery, Kimbrel was coming off the side of the ball a bit, causing him to lose a little velo. In 2021, he’s kept the hand behind the ball, and that has helped him drive through it. That’s pushing velo up and that natural trailing hasn’t been as pronounced.

There are only a couple ways to improve velocity; mechanics, mobility, and effort. Kimbrel has made changes in all three areas.

In 2019, Kimbrel visited the IL with a couple of issues. The first injury was a knee inflammation and the second was a stint in September with right elbow inflammation. These injuries, even after he may have recovered from them, limited his mobility and didn’t allow him to rely on mechanics to be successful. I’d even suggest the knee issue helped cause the elbow issue later in the season. But with more freedom in his delivery, Kimbrel was able to recapture fluidity, likely mechanics, and thus, velocity.

The next area I see from Kimbrel is more physical force or effort.

This isn’t to say that Kimbrel wasn’t throwing with effort in 2019, but just watching his effort through the ball it seems as if he is (for the lack of a better term) just trying to throw the ball harder. This is evidenced by his release speed, which is recorded on Brooks Baseball.

Now, you can worry about if he can maintain the effort through a full 162-game season, but I would point back to the fact that he’s cleaned his mechanics and is free of injury. If those are true, then the “effort” shouldn’t have an impact on his availability day-to-day.

So… if he “better than ever?” Well, it’s damn close!

Kimbrel’s 0.66 ERA is the lowest of his career, which beats his 1.01 in the 2012 season (he posted a 0.44 ERA in his rookie season, appearing in 22 games). Since Fangraphs recorded xERA, his 1.86 xERA is the best of his career (2.09 in 2015). Kimbrel’s 2.13 xFIP in 2021 would represent the fifth-lowest of his career. He’s also on pace to eclipse his highest fWAR of his career, already posting 1.5 fWAR through 27.1 innings.

But it is more than just that, Kimbrel’s stuff has been special. Hitters have to respect his fastball so much that they’re consistently swinging at curveballs thrown only 50 feet. They’re starting their bat up so quickly to cover themselves for the heater so much that Kimbrel is getting away with balls out of the zone, consistently. This has improved his BB/9 to 2.96, which would represent the third-lowest mark of his career.

He has been so special, that even when hitters are putting balls in play, they’re 110 points below league average (.191 babip).

Whether he is as good or better than he’s ever been I don’t know sure certain. It seems as if he is posting numbers at rates that would push his career bests and certainly put him in the “best closer in the game right now” conversation. Putting an end cap on his career, with a season like 2021, will certainly help to put him in Cooperstown when he retires. The question now is, will it be enough to win games in October for the Cubs? Time certainly will tell.