Advanced stats from 2021 that matter for St. Louis Cardinals

Nolan Arenado’s abnormally high pull percentage (45.8%)

Even by the end of the season, it’s unclear if the shock and awe of having Nolan Arenado finally in a St. Louis Cardinals jersey had worn off. Though his batting average and OPS dropped from his time in Colorado, Arenado was the first Cardinal since Matt Holliday in 2012 to reach 100 RBI and his defense was as advertised.

He’d be the first one to tell you he expected better in his first season in St. Louis, but I don’t think many fans were complaining about having him anchoring the cleanup spot in the lineup. Digging deeper into his full season of batting stats reveals something interesting though: Arenado pulled the ball more than ever in 2021.

For his career, Arenado has a Pull%/Straight%/Oppo% slash of 39.9%/37%/22.8%. He could be described as a pull hitter based on that, but in 2021 that line jumped to 45.8%/33.3%/20.8%. A full 5% jump in pull percentage is really what jumps out here, especially when you combine it with the knowledge that every single one of his homers was pulled to left field.

In 2020, Arenado had a down year at the plate during the shortened season and it was revealed by Arenado himself that he had been playing through a shoulder injury for most of the year. According to MLB.com’s Thomas Harding in the article linked above, “The pain [was] inhibiting his ability to “lift” the ball with his swing.”

I’m not going to go full out onto a limb and say that Arenado’s shoulder is still injured, but a change as large as fans saw in 2021 when talking about pulling the ball could mean that the injury changed his swing mechanics, or impacted it in some other way that could still improve over time. This change could also be explained by a change in approach, the pressure he’s putting on himself to perform, or any number of other reasons that could be just as plausible. All I am arguing is that this change in batted ball profile needs some attention, regardless of the reason.