Is Jay Bruce Having a Breakout Season or Just Another Brief Hot Streak?

Jay Bruce is off to a great start at the plate this season. Is it just another of Jay’s patented hot streaks to be followed by the inevitable cold streak? Or has Bruce truly made some adjustments that will enable him to finally have that consistent, MVP-caliber season we have been hoping for (or expecting) ever since he was the consensus #1 overall prospect in all of baseball in 2008? Let’s take a look under the hood for clues…

Jay has had only 36 plate appearances so far this year. That is a ridiculously small sample size from which to draw any meaningful conclusions but who cares? We are doing this for fun not for science. We can track these metrics throughout the season to see how he is doing.

Jay’s numbers look great after the first 9 games. All of his rate stats are well above his career norms. This much is obvious. We will have to dig a little deeper to see what is causing his success and find out if it is sustainable.

Bruce has always hit the ball hard. This year is no exception. This good Hard Hit rate is perfectly normal for him. His Soft Hit rate is slightly better. This chart doesn’t really help us determine why his numbers have been better than usual though.

This chart is interesting. We can see that Jay’s pull rate has dropped significantly. He is hitting the ball to the opposite (left field) side a little bit more than normal. He has been hitting the ball up the middle almost half the time he makes contact. That is a major change from his normal spray chart. It is still very early in the season to be certain, but it appears that Jay has made some changes to his stroke that have manifested themselves in his results. If this continues we should see opposing teams discontinue the extreme defensive shifting they have employed against Bruce in recent seasons.

This chart is nice to see. Bruce’s line drive rate is spectacular this year, nearly doubling his career average. He is squaring the ball up and drilling it up the middle for base hits. Two years ago in 2014 when Jay was playing with a knee injury his ground ball rate was 45% because he had no leverage in his swing. Last year his ground ball rate returned to normal and his fly ball rate spiked to 44.2%. He has cut that down by 10 percentage points so far this year. The combined effect is a massive increase in line drives. That is a good thing, because throughout baseball in recent seasons hitters have put up a batting average of  .724 on line drives. This is great news for Bruce this year if he can maintain a similar batted ball profile throughout the season.

This could provide a word of caution at first glance, but it really shouldn’t. Batting Average on Balls In Play can give us a clue about whether a hitter has gotten lucky with fluke hits on poorly struck balls dropping between fielders. Jay’s career BABIP of .287 is a bit below the league average of .295 but part of that is because he has always been a fly ball hitter. Fly balls only fall in for hits about 13.8% of the time (.138 batting average). Ground balls become base hits 23.7% of the time. So a player like Bruce who hits more fly balls than ground balls is likely to have a BABIP slightly below average, as Bruce does for his career.

You will notice that Bruce’s .251 BABIP last year was extremely low. It turns out he was very unlucky last year. His xBABIP, or Expected BABIP as calculated by multiplying his batted ball profile by their normal batting averages ((GB% * .237)+(FB% * .138)+(LD% * .724)) shows his BABIP last year should have been .284 given normal luck. This means Bruce actually hit better than his .226/.294/.434 slash line and 91 wRC+ indicated. It does not mean he hit like a star, but more like a league average hitter than the 9% below average hitter his 91 wRC+ indicates.

This year his xBABIP is .351, which closely matches the .360 we see in the chart. So we should not say Bruce’s hot start is the result of mere good luck caused by fluke hits on weakly-hit balls in play. His BABIP is high this year because it should be high due to his excellent line drive rate. His career xBABIP is .291, which again is very close to the .287 career BABIP in the chart.

Bruce is not likely to continue to hit line drives 30% of the time. League average is 20%. Joey Votto’s career LD% is 25.3%. It would be unrealistic to think that Jay Bruce is going to keep hitting more line drives than Joey Votto does. Brandon Belt of the Giants led the majors last year with a 28.7% line drive rate. So we can safely say that Jay Bruce is not going to maintain his current 30.4% line drive rate over the course of the full season. But there is a good chance that Bruce will be able to maintain a good chunk of his improvement. This transformation might be real.

Conclusion

Jay Bruce is off to a legitimately hot start at the plate. It is not a fluke. He has been hitting the ball squarely in the middle, resulting in a high rate of line drives to center field. He isn’t hitting the ball hard any more often than he always has, but he is hitting it squarely rather than pounding it into the ground or hitting it high in the air. This bodes well for his stat line this season. It is still a small sample size of plate appearances, but we are rapidly approaching the time when a hitter’s batted ball profile begins to stabilize. If Bruce continues to hit the ball in similar fashion we can comfortably say that the change in profile is due to some adjustments he has made to his swing or his approach that have manifested themselves rather than random variation (luck). I think this is a positive sign that this might not be just another brief hot streak, but rather a sustainable performance improvement.

If it is a real improvement it will not only help the Reds win more games this year, it will also make Jay Bruce into a much more valuable trade commodity than we thought over the winter.