I am not sure if I first fell in love with Yandy Díaz when I saw his arms or when I saw his plate discipline, but there is something about a guy with the strength to demolish baseballs and the patience to take a walk that just makes my baseball heart flutter. The problem for Díaz has always been that he uses that extreme power to hit the grounders instead of dingers – and dingers are better than grounders.
And so all through the minors, Díaz put up impressive lines. From 2014 in High-A through 2017 in Triple-A, he never put up a wRC+ lower than 123 at any stop when he got at least 20 PA. That 123 was his pro debut – after that he was 143 or over at every stop. But he did that without much in the way of power. He had 23 HR in 1,821 minor league PAs before his MLB debut in 2017. But when you regularly run walk-rates well over 10% and strikeout rates under 20% and challenge minor league defenders with smoking hot ground balls, you are going to put up impressive numbers, even without the homers.
Despite that, Cleveland never seemed ready to give Díaz a real shot (299 total PA in 2017 and 2018) and sent him off to Tampa Bay for Jake Bauers and cash. Díaz then hit 14 HR in 347 PA for the Rays in 2019, a huge jump in his power output.
How does a guy go from hitting just a handful of home runs a season to a 25-homer pace? Players generally increase homer output by either a) hitting more fly balls or b) hitting fly balls harder so that more of them turn into home runs. In 2019, Díaz did both.
Look at his HR/FB rates and FB% for each stop in his Minor and Major league career and you see he sometimes posted decent HR/FB rates and sometimes posted decent FB rates, but never both at the same time until 2019, when he suddenly posted career highs in both. And not just major league career highs, but professional career highs.
The Break Down
But let’s update that table and add in 2020 and the first month of 2021 (we’ll get to the rest of 2021 soon enough).
In 2020 the fly balls dried up. Completely. An 11.3% flyball rate is almost laughably low. Since 2000, there have been 8,669 player-seasons of more than 100 PA. 11.3% is the third lowest FB rate. If we focus just on the last nine seasons – the era during which launch angle started to become a focal point for hitters – it is the lowest. In the last five years, only five players have had a 100+ PA season under 15% and no one else has been under 12%.
What did this power roller coaster do to Díaz’s perceived fantasy value? In 2019, his NFBC ADP was over 500, which was not a surprise – he wasn’t a known entity, didn’t have a clear job, and was projected to have little power and no real speed. Coming into 2020 he was being drafted in the top 250 at NFBC. Not a stud, by any means, but pretty good for a guy who still figured to have only a part-time role with platoon-happy Tampa Bay. By the start of the 2021 season, his NFBC ADP was back up to almost 600 – even worse than it was before 2019. The 2020 ground-ball-a-palooza clearly convinced the crowd that Yandy was still the same old Díaz.
Early this year, players who passed on Díaz in drafts likely felt vindicated. As of June 5, Díaz had hit zero (0) home runs in 2021. His FB rate had crept up but it wasn’t as high as it was in 2019 and there were a number of other worrying signs. Through 2019, his career average exit velocity was 91.7 mph. That dipped to 88.3 in 2020 and was only 88.8 through June 5 of this year. His hard-hit rate (46.3% coming into 2020, but just 30.9% in 2020) was down at 33.8%. His barrel rate (6.5% coming into 2020, but just 2.1% in 2020) had rebounded to 5.0% but was still far short of the 9.2% he posted in 2019.
The Breakout Part II: The Return of Yandy
Then on June 6, something happened. What it was, I honestly have no idea. Well, sort of. I know that Díaz finally hit his first home run of the season.
What I don’t really know is why Díaz suddenly found his home-run swing and took off, but he definitely did.
Going into this game, Díaz had an average launch angle of 2.5. That isn’t good, but it also isn’t unexpected from him, unfortunately. In his four MLB seasons prior to 2021, his average launch angles were 0.0, 4.4, 5.7, and -7.9 (yes negative seven-point-nine). Even that 2019 number – 5.7 – is way too low for a guy with the kind of explosive power he has.
But there was nothing wrong with the launch angle on that one. And there hasn’t been anything wrong with his launch angle since then.
There is a really interesting story on that graph. Díaz came up with a clear ground ball issue that needed to be addressed and, through 2019 he was making steady progress getting the ball into the air more often. Then 2020 happened, as it did for so many players, and that progress was reversed in a major way. But in 2021, he has basically put himself back on the track he was on through 2019.
In fact, Díaz pushed his rolling average launch angle above league average for the first time in his career on May 19, and while it was back down below average the next day, he’s been hovering around that line at 12% for a couple of weeks now. A couple weeks of league average launch angle might not seem like a ton to get excited about, but it represents a new phase in the career of Yandy Díaz. For years, his fans have been waiting for him to consistently elevate the ball, and he is finally doing it.
Earlier we mentioned that after finally combining an increase in fly-ball rate with a high HR/FB rate for the first time in his career in 2019, he lost the fly balls in 2020 and lost the HR/FB rate early in 2021. Since June 6?
Of course, that only matters if there are results. And, oh yes, there are results. Since June 6, he has seven home runs in 153 PA, which is a lot better than zero homers in 223 PA before June 6. Over a full season, that is a roughly 28 home run pace. But Díaz isn’t pure power – he is still walking 10.5% of the time and striking out only 18.3% of the time. Those are both worse than what he was doing earlier in the year but are still quite good. Justin Turner has a 10.3% walk rate and a 17.0% strikeout rate. That’s pretty good company.
Over this stretch, Díaz has a 121 wRC+, despite a low-for-him .333 OBP (held down by a .275 BABIP, well below his .334 career mark). That BABIP may be down in part because he is lifting the ball more, but I suspect we’ll see some positive regression there.
I said I don’t know what drove this improvement, but we can look at some of what Díaz and his manager, Kevin Cash, said before the season for some clues. Back in February, Díaz told Adam Berry, Rays beat writer for MLB.com, that, “My goal is to be the Yandy of 2019.” This included putting the ball in the air more and hitting for more power.
In the same piece, Cash noted that injuries had taken their toll on Díaz in 2020, and Díaz himself said that after the injuries, he needed “to try to get back and get that strength that I need.”
Put together, it sounds like Díaz came into camp a) looking to get the ball back in the air and b) still working to get the power back in his swing. The numbers we have seen – the early increase in fly ball rate; the later increase in HR/FB rate, would seemingly match that. He made the changes to his approach immediately, but it took a little longer to get the home runs to come back, too.
If the changes in launch angle stick, Díaz is a super interesting player moving forward. If he can put up a 25+ HR pace with a solid average (.272 for his career) and an excellent OBP (.364 for his career), plus the runs and RBI that come with hitting in the top half of a solid lineup, there is a lot to like.
Diaz has started more often than not for Tampa – the team loves platoons and utilizes their deep bench to manage matchups, but since 7/25, Díaz has started all but two games, which helps buoy his value a bit. In deeper leagues, where you can use him as a part-time player, particularly OBP leagues, I would be adding him immediately if you need help at the corners (he qualifies at 1st and 3rd in almost all formats). In shallower leagues, where you don’t have deep benches, I am a bit more hesitant, but he is still a guy I would be looking closely at.
Photo by Cliff Welch/Icon Sportswire | Adapted by Doug Carlin (@Bdougals on Twitter)