I don’t need to tell you that the Indians are a very good team. I also don’t need to tell you that the Indians are great at finding hidden talent. Well, this is another good player. Surprise. In a farm system containing two of the best prospects in baseball (Triston McKenzie, Francisco Mejia), along with other intriguing talents like Bobby Bradley, Yu-Cheng Chang, and a personal favorite of mine, Nolan Jones, it can be easy to get overlooked. It’s difficult to maintain success as a smaller market team, but the Indians have positioned themselves well for the inevitable massive paydays and arbitration raises their young core will require. You can obviously see the difficulties in being a small market team and building a consistent winner (see: Royals), but a lot of organizations are building value through non-prospects, utilizing advanced statistics and investing in player development.
Last year, Fangraphs’ Eric Longenhagen ranked Yandy Diaz twelfth (45 FV) in a pretty interesting system, praising his plus defense at third base in addition to his cannon of an arm which Longenhagen gave a 70. Diaz has long been an interesting player, running up higher than a 140 wRC+ every year, including a 163 wRC+ at AAA last year. So for now, let’s take a look at the minor league version of Yandy Diaz.
Last year, Diaz walked 16% of the time while only striking out 15% of the time. That is incredible. He also walked a stunning 21.8% of the time at AA in 2016. The type of profile you see forming is someone with a pretty excellent ability to make contact but with a decent amount of authority. You can tell he’s got a pretty strong ability to control the strike zone, and generally with that you see guys that can make hard contact since they tend to be more selective. If we consider these basic tenets without knowing anything else about this profile, you can assume he’d have a high BABIP. Sure enough, last year at AAA, Diaz ran a ridiculous .412 BABIP. Last year before that, .381. The three levels before that were all .320+.
So, here’s the thing. Yandy Diaz is a bit of an oddity. For someone with his profile, he does not hit like you think he does. You would assume due to the consistently high BABIP’s and low strikeout rates he’d be a line drive hitter. He kind of reminds me of Dustin Pedroia. Dustin Pedroia is a line drive hitter. I wouldn’t really describe anyone as a ground ball hitter, but this is what Yandy Diaz is. Think of the most ridiculous ground ball percentage you could think of. I thought of around 55%, looked at Eric Hosmer, and he was at 55.6% last year. Hosmer was fourth in GB% amongst qualified hitters. The leader was Dee Gordon at a poor 57.6%. Yandy Diaz was at 63.5% in AAA.
A quick Excel calculation of qualified hitters last year gives us an average GB% of 42.62%. With a sample of 144 hitters, we arrive at a standard deviation of ~6.4%, giving us an overall Z-Score of 3.26479 for Yandy Diaz. So what does this all mean? Let’s take a look at the graph below.
The center line of the graph is the mean, or in our case 42.62%. Each player varies an average of ~6.4% on ground balls. Still, what does this mean? Well, as you can see, there are standard deviations on both sides of the mean. So, for example, a player left of the mean is more of a fly ball hitter, and a player on the right is more of a ground ball hitter. We’ll refer to these as bounds.
68% of all players will be somewhere in between Jackie Bradley Jr. and Didi Gregorious. Let’s expand that to two standard deviations. It’s hard to see many more players hitting ground balls than Christian Yelich, and it’s tough to find hitters who hit more fly balls last year than Jed Lowrie. That’s because 95% of players will fall in between these two. There are a lot of factors that decide what a statistical outlier is (the boundaries are always set by the person doing the math, it isn’t a one size fits all thing), but for the sake of me not going down a rabbit hole, let’s consider anything about a Z-Score of 2.0 an outlier since only 5% of the population will fall outside of Yelich and Lowrie.
A Z-Score of 3, or three standard deviations away from the mean, has 99.7% of the population within its bounds. Nobody accomplished a 61.8% ground ball rate last year, and nobody had 23.4% on the other end. If Yandy Diaz’ GB% of 63.5% was in the majors, he would have been a part of that 0.3%. If you look at the graph and see the watermark for “MathBits”, it basically covers that ~0.15% because nobody hits as many ground balls as Yandy Diaz.
I don’t know if you’ve noticed what’s been going on with baseball the past couple years, but teams and players alike are finding that ground balls aren’t very valuable. In fact, high ground ball hitters have extremely unpredictable profiles since the variance in the variety of outcomes is higher than any other batted ball type. I stole this next picture from Fangraphs’ glossary, and it is a little outdated (2014), but the general importance still stands.
Ground balls are by far the least valuable of the batted balls. You knew this, I knew this, but now we get to see how significant it is. You can’t be a very valuable hitter with 63.5% ground balls. This is an issue. Yandy Diaz would be an interesting player in any organization, but becomes more interesting with the Indians. This is a smart front office. One that uses statistics and science to continue to develop players. Two players who weren’t ever supposed to be power threats just hit a combined sixty-two home runs last year (Lindor and Ramirez).
Here’s what’s exciting about Diaz. I talked about his consistently high BABIPs, saying there’s a good chance he hits the ball pretty hard. He hits the ball pretty hard. Of batters with one hundred batted ball opportunities, Diaz ranks 69th, sandwiched in between Ketel Marte (68) and Tyler Flowers (70) at a cool 112.8 MPH for maximum exit velocity. Now, you might be thinking Ketel Marte and Tyler Flowers? Well, Marte has been written about (me first, and then a better article later by Jeff Sullivan), and Flowers was one of the most improved hitters in baseball last year after a swing change. Other notable hitters that are at or below Diaz are as follows: Cody Bellinger (112.8), Kris Bryant (112.5), Paul Goldschmidt (112.4), Carlos Correa (112). That’s some good company in addition to many other above-average, quality big leaguers in that range. In terms of average exit velocity?
He ranks seventh.
Tied with Paul Goldschmidt, and just behind Giancarlo Stanton.
So that’s pretty good. An average exit velocity of 91.5 MPH is elite. You’re talking about potential 30-40 HR power here. All this untapped power, yet an incredibly poor barrel ranking. In terms of Brls/PA, Yandy Diaz is at 2.2. Stanton and Goldschmidt are at 11 and 8.1 respectively. In terms of average ground ball velocity, Yandy is first in baseball and it’s not particularly close. He sits at an average of 90.8 MPH, with the next highest being Gary Sanchez at 88.3 MPH. Remember when I said ground ball heavy profiles are tough to predict? Well, nobody hits the ball as hard as Yandy does. Shockingly, he may be able to run a ridiculous BABIP bludgeoning ground balls past defenders. And he’ll likely give second basemen hell because, oh yeah, he went to the opposite field 47.9% of the time at AAA for some reason.
As if there weren’t already enough reasons to love this guy, in his big league stint he ran an O-Swing% of 15.6%. Joey Votto ranked first in baseball with 15.8%. We’re potentially looking at one of the most selective hitters in baseball. His overall Swing% of 38.9% would have ranked within the top ten in baseball. This top ten is a fairly eclectic group, but all are safely above-average hitters. All his plate discipline numbers really stick out, however his SwStr% is very impressive at 6.4%. This would have made him twenty-first in baseball, tied with Justin Turner and Alex Bregman.
Steamer, love it or hate it, generally provides a rough estimate of where a guy stands entering the season, though it tends to be conservative. It predicts a .289/.373/.402 slash line for Diaz, with a 109 wRC+. Not bad. Most lineups will take a guy with a .370+ OBP. Xander Bogaerts is also projected for a 109 wRC+ with a .289/.353/.445 projected triple slash. This is how Steamer sees Diaz right now. But imagine what unlocking some of that power would do for his profile. It’s not hard to see Diaz with 20+ homers as soon as next year, especially with the current offensive environment we’re in. Throw in a bunch of hard doubles, and you start to see the makings of an offensive monster. The Indians were one of the biggest beneficiaries of having a couple guys change their launch angles, and just brought on Yonder Alonso, presumably to keep working with the strides he made last year with the Athletics.
There’s obviously a ton of offensive potential here with Diaz, and it’s not difficult to see him becoming a star. However, making a ground ball hitter who goes up the middle and the opposite way suddenly start pulling the ball with lift is where the challenge lies. Of course, this isn’t even giving Diaz enough credit with his overall profile; he looks like a potential plus glove at third with a cannon for an arm. With Francisco Mejia rumored to be the likely answer at 3B (he somehow has MORE of a cannon for an arm), Diaz could become one of the most valuable utility men in baseball, even with a 109 wRC+. Of all the players I’ve written about breaking out this offseason, Diaz excites me the most. He may just be the next player to break out for Cleveland in a big way.