Bryce Harper’s Weakness

Few players can hold a candle to Bryce Harper. At an age where most kids are still in college, Harper has already emerged as one of the best players in baseball. After a strong rookie year, Harper has taken a step forward in year two. His walk rate is up, strikeout rate is down and his .378 wOBA is 20 points higher than last season. There is, however, one area where Harper has looked mortal. In his first season-and-a-half in the majors, Harper has shown a significant platoon split.

Following a groundout during Saturday’s game, Adam Kilgore of The Washington Post pointed out the issue on Twitter. While Kilgore’s tweet only dealt with this season’s struggles, Harper also had a difficult time against lefties during his rookie year.

Career numbers	PA	BB%	K%	AVG	OBP	SLG	wOBA
Lefties	270	8.9	25.4	0.219	0.290	0.370	0.291
Righties	540	11.5	16.8	0.294	0.377	0.550	0.396

For the most part, the table shows that Harper has been much worse against left-handers over his brief career. At the same time, it’s important to point out that we’re dealing with an incredibly small sample size here. Harper has only faced lefties in 270 plate appearances. That’s hardly enough to be a huge concern, but opposing managers have started to take notice.

The main issue for Harper appears to be low and outside against lefties.

Harper is hitting below .100 on the three squares in the bottom-left corner. Remember, the BrooksBaseball.net charts are from the catchers point of view, so the bottom left corner would be outside to a lefty. Breaking pitches have given Harper the most trouble off the plate low and away. In those same three squares, Harper has gone 2-38 on “breaking pitches” over his career. Breaking pitches include sliders, curveballs, slow curveballs and knuckleballs. Pitchers have taken notice of Harper’s struggles with breaking stuff low and outside. He’s only seen 19 “hard pitches” in that area and four “offspeed pitches” in that area over his career from left-handers.

While it’s easy to suggest Harper’s average would be low on pitches outside of the strike zone, that’s not the only explanation for his struggles. Harper has shown high swing rates on breaking balls low and outside. He’s had a tough time laying off those pitches. As expected, his whiff rates are high in that area. He’s whiffed at a whopping 52.08% of breaking pitches thrown in the box directly below the outside corner in his career.

Given Harper’s age and lack of experience, it’s not surprising that there are still things he needs to work on. And since we’re just working with 270 plate appearances, there’s no major reason to panic just yet. Harper has never seen stuff this good from left-handers, and it makes sense that he would need some time to adjust. The league is likely aware of the issue, and Harper is going to see his fair share of late-inning left-handers coming out of the bullpen. But in his case, more experience is a good thing. Even with the struggles against lefties, Harper has become one of the most feared hitters in the game. Once he figures out how to lay off on pitches low and outside, the league is going to be on high-alert.