Tyler Flowers Has Been the Most Underrated Player in Baseball

Thanks to improvements at the plate and his usual excellence at stealing strikes, Tyler Flowers has been one of the most valuable players in the game this season.

One of the top performers in baseball this year has hardly gotten any national attention, probably will not get an MVP vote at season’s end and is not even on track to be voted into the All-Star Game.

Yet few players have provided more value to their team than Atlanta catcher Tyler Flowers. The 31-year-old had something of a breakout last season, and has built off of it in 2017, compiling a .325/.427/.478 slash line (144 wRC+). He has also hit six home runs in 185 plate appearances.

Flowers has been worth 1.7 WAR at FanGraphs and 1.6 WAR at Baseball-Reference, tying him for 55th in the former and for 72nd at the latter. Neither figure, though, accounts for pitch framing.

Baseball Prospectus’ WARP does, which is why Flowers is tied for ninth by that measure of value. At BP, Flowers has been worth 3.3 WARP, putting him in between Mike Trout and Buster Posey. This is already a career high, surpassing his 2.6 WARP campaign from last season.

He has coupled the value provided with his bat with his usual proficiency in terms of stealing strikes. In that regard, he has been worth 10.7 runs above average, behind only Yasmani Grandal. By’s measurements, he has actually been the best catcher, getting 111 more strike calls than expected, which has been worth almost 15 runs above average. This more than outweighs a subpar caught stealing rate.

Improvements At the Plate

Flowers has always been a strong pitch framer, but had never sniffed the upper echelons of the WARP leaderboards, due mostly to an inability to get on base. He had generally run a high BABIP, but was done in by low walk rates and sky-high strikeout rates.

He came into this season with a .322 career BABIP, but a 32.3% strikeout rate and a below-average 7.1% walk rate. During this span, only six players struck out at a higher rate. Prior to the start of this season, his career slash line was .232/.302/.384.

Things began to click last season, his first in Atlanta after seven seasons with the White Sox, as Flowers notched his first big league season with an above average wRC+ (110). The strikeouts were still there (on 28.0% of his plate appearances), but he was able to couple a .366 BABIP with his first above-average walk rate since a 38-game stint in 2011.

The BABIP was obviously higher than we should expect, but it was driven in part by solid contact. His xBABIP was .329, per Andrew Perpetua’s, which analyzes Statcast data. He also nearly halved his infield flyball percentage, putting up a rate of just 5.3% (which was tied for 39th lowest among the 268 players who had at least 300 plate appearances).

In 2017, he has built on this further, racking up a higher walk rate (9.2%), xBABIP and real BABIP, while mixing in a 20.0% strikeout rate, the lowest of his career. And it’s the lowest by a long shot:

Looking Ahead

I think it’s safe to say Flowers will not keep running a .395 BABIP for the duration of the season. Keep in mind, though, we should also probably not expect him to post a .300 BABIP going forward either.

As mentioned, Flowers has run higher than average BABIPs for his whole career, and his xBABIP is .346 in 2017. Even more encouragingly, ZiPS projects him to run a .348 BABIP for the rest of the season and Steamer has his rest-of-season BABIP pegged at .328.

Both models have him providing roughly average value with his bat going forward (which is better than most catchers can say), and the combination of that with his framing value means he should be expected to be a firmly above-average player going forward.

"Firmly above-average" is different, though, than "Top 10 player in the game." This is because neither model is buying into his strikeout or walk rate improvement. It makes some sense, given we have roughly 1,400 plate appearances suggesting these are weaknesses in his game. Players in their 30s tend not to show drastic improvement.

Then again, we are talking about walks and strikeouts, two stats which tend to stabilize quicker than most others. In 2012, in what has to be one of the most-cited articles in stathead circles, Russell Carleton found that strikeout rate stabilizes after 60 plate appearances and walk rate becomes reliable after 120.

Flowers has 185 plate appearances with a 20.0% strikeout rate this season, and he has a 9.0% walk rate over his last 510 plate appearances, dating back to the start of last season. More granular per-pitch stats imply this is the result of an improved process at the plate.

He is swinging at about 26% of pitches out of the zone, below the league average of 30%. This is his lowest rate since he started getting regular playing time in 2011 and marks the continuation of a trend that began in 2015.

When he does swing at these pitches, he has made contact 68% of the time, marking the first time he has been above average here as a big leaguer. He is also only swinging and missing at 8.7% of all pitches, which -- you guessed it -- is the first time he is ahead of the major league average.

Because these statistics are scaled on a per-pitch, rather than a per-plate appearance basis, sample sizes build up more quickly. This, in turn, helps them stabilize quicker and become more reliable.

They also correlate highly with walk and strikeout rates -- Jeff Zimmerman found that zone and outside-of-zone swing and contact rates explain 89% of the variation in strikeout percentage and 79% of the variation in unintentional walk rate.

Since Flowers has shown improvement in these areas, it is easier to be confident his improved approach is "real." He may not maintain his exact to-date levels, but it is also not hard to see him beating his projections.

Combine that with solid performance on balls in play, and elite pitch framing, and you have a pretty good ball player.

It wouldn’t kill you to throw an All-Star vote his way.