How Long Can Zack Cozart Keep This Up?

Known mostly for his defensive work, Reds shortstop Zack Cozart has become an offensive force, and one of the most valuable position players in baseball this season.

One of the many reasons why baseball is awesome is the fact that the game never ceases to surprise us on any given day or year. There have been quite a few examples of that so far in 2017, but perhaps none better than Cincinnati Reds shortstop, Zack Cozart.

Entering action on Monday, June 5th, who would be your guess as the National League position player with the highest fWAR?

Charlie Blackmon is making waves as the Colorado Rockies' leadoff man. Both Ryan Zimmerman and Eric Thames got off to insane starts during the month of April. Paul Goldschmidt has been busy reclaiming the MVP-caliber form he showed in 2015. And, oh yeah, there's some dude named Bryce Harper who's been pretty good.

Those would all be good guesses. They'd also all be wrong.

If you're like me, you didn't believe the above tweet. I had to head over to FanGraphs to see it for myself. What a time to be alive.

As it stands right now, the only position player with a higher fWAR than Cozart is Mike Trout (3.4). That's spectacular company for a player who has never posted a wRC+ over 100 (league average) in a full season since becoming an every-day player in 2012 (he was limited to 53 games in 2015, so his 105 wRC+ doesn't count). What the heck happened here?

Taking Things Up a Notch

The 2016 season appears to have been a stepping stone to this dominant start. In 508 plate appearances, Cozart slashed .252/.308/.425 and set single-season career highs in wRC+ (91), wOBA (.312), home runs (16), hard-hit rate (31.2%) and fWAR (2.5).

So far in 2017, though? Well, let's just say things have escalated quickly. His triple slash is a healthy .344/.432/.622 through 213 plate appearances, and it's accompanied by a 173 wRC+ (third-best in the NL), .439 wOBA (also third-best), 9 homers, a 30.8% hard-hit rate and that NL-leading 3.1 fWAR.

It's not as if he's sacrificing anything in the field, either. He's consistently been an asset with the glove for Cincinnati, and currently ranks within the top 10 in baseball at shortstop in both defensive runs saved (3) and ultimate zone rating (4.7).

If we put this all together and tie it up in a neat little bow, Cozart's performance over the first two months this season has been worth $24.9 million, according to FanGraphs. And in case you were wondering, that's already more than any other season in his big league career.

A Slow Change in Batted-Ball Events

Just by looking at Cozart's stat page, it's easy to point towards the shortstop's improved plate discipline -- which has resulted in a 14.1% walk rate -- for the leap he's made this season, but there's also been a gradual change in his batted-ball profile. He combined to hit 27 homers between 2012 and 2013, but then combined for just 13 over the following two seasons before hitting 16 last year.

If we look at how certain parts of his game have fluctuated over the years -- mainly line-drive rate (LD%), ground-ball rate (GB%), and fly-ball rate (FB%) -- it shouldn't be all that surprising.

Year PA LD% GB% FB%
2012 600 20.0% 41.7% 38.3%
2013 618 18.0% 50.3% 31.6%
2014 543 17.7% 44.6% 37.7%
2015 214 19.3% 38.6% 42.2%
2016 508 20.6% 39.4% 39.9%
2017 213 21.2% 37.0% 41.8%

It hasn't been a steady rise or fall every year, but we can see each of these batted-ball events slowly changing. His line-drive rate and ground-ball rate are on pace to be career bests, while his fly-ball rate is awfully close. And if we throw out that injury-shorted season of 2015, it would also be on pace to be a single-season career high.

Even though the change from year-to-year in the above table is clear, it's also not as if any one category has changed drastically from last year. What is different, though, is his BABIP.

Can Cozart Keep This Going?

Entering 2017, Cozart never produced a BABIP higher than .285 in a single season. That occurrence took place back in 2013, and his .274 BABIP from last year is basically on par with his career numbers.

Among qualified hitters this year, his .387 BABIP is tied for the sixth-highest mark in all of baseball, finding himself in a tie with Xander Bogaerts and Corey Dickerson. And if we look at some of his results on the three batted-ball events we've been discussing and compare that to 2016, he's seen a substantial boost.

Cozart's hard-hit rate on ground balls is currently 24.1%, which would be a career high, but so would his soft-hit rate, which is 29.6%. Despite that, he's managed a wRC+ of 90 after posting a mark of 37 last year. While he produced a wRC+ of 100 on fly balls in 2016, his current 221 mark is inflated to begin with, especially since his hard-hit rate is currently lower (34.4% in '17, 35.3% in '16).

This trend continues with line drives, but it's even more pronounced. His 9.7% soft-hit rate isn't far off from 2016 (8.9%), but his hard-hit rate has taken quite a dip (48.1% in '16 to 35.5% so far in '17). Despite that, his wRC+ currently sits at 406 after settling in at 282 last year.

We Might Have Seen This Story Before

Does Cozart getting off to a hot start sound familiar at all? That's because there were probably people talking about it last year, too.

Only two of his 16 homers from 2016 came during the month of April, but it was by far his best month of the year -- he posted a .911 OPS with a .378 wOBA and 134 wRC+ off the strength of a .387 BABIP. From May to the end of the season, though, those numbers dipped to .700, .301, 83 and .252, respectively.

While we don't want to discount the hot two months Cozart has experienced thus far, it's could still be up for debate as to whether he's creating a new normal here, or just on a prolonged hot streak compared to what we saw last season.

Either way, if you predicted back in April that he'd have the highest fWAR in the National League on June 5th, you win. Then again, there's no way I'd believe you.