The '21 rising star you might have missed

September 19th, 2021

The best hitter on the best team in the American League West right now is probably the last Astro you think of. But there should be no hiding .

Yes, Tucker has really been the best bat in the Astros' lineup this season. And their lineup has been very good. Not to mention it's full of bigger names like Carlos Correa, Jose Altuve, Alex Bregman, Yordan Alvarez, Yuli Gurriel and Michael Brantley. But the 24-year-old lefty-hitting outfielder is the one who leads the team in the key overall offensive stats.

Best Astros in OPS, wRC+ and wOBA in 2021
Kyle Tucker -- .908 OPS | 147 wRC+ | .378 wOBA
Yordan Alvarez -- .886 OPS | 142 wRC+ | .373 wOBA
Carlos Correa -- .847 OPS | 136 wRC+ | .363 wOBA
Yuli Gurriel -- .842 OPS | 135 wRC+ | .362 wOBA
Jose Altuve -- .842 OPS | 132 wRC+ | .359 wOBA
Alex Bregman -- .824 OPS | 129 wRC+ | .355 wOBA
Michael Brantley -- .808 OPS | 127 wRC+ | .350 wOBA

Tucker is one of only 14 qualified hitters in MLB this season with an OPS of .900 or higher. His 147 wRC+ means he's been almost 50% better than a league-average hitter, and makes him a top-10 hitter in baseball. His .378 wOBA (an all-encompassing number similar to on-base percentage, except more value is given to bigger hits, like home runs) is top-15 in the Majors.

If the Astros' lineup is firing on all cylinders, they're going to be a major threat in October -- and Tucker will be one of the major threats in that lineup. Here's a closer look at what he's doing.

Elite contact
Tucker's numbers are for real. His quality of contact has been elite all season. For a lot of the first half, though, he was one of the unluckiest hitters in baseball -- his actual stat line was much worse than what would be expected based on his contact quality. But now he's maintained that high level of contact into the postseason push, and his numbers are reflecting it.

Here are Tucker's expected stats for the season, which come from his Statcast hitting data, along with his actual stats.

.312 xBA / .584 xSLG / .403 xwOBA
.297 BA / .555 SLG / .375 wOBA

Tucker ranks second in MLB, out of 311 qualifiers, in expected batting average, behind only Freddie Freeman. He ranks sixth in expected slugging percentage, behind Fernando Tatis Jr., Bryce Harper, Shohei Ohtani, Ronald Acuña Jr. and Vladimir Guerrero Jr. And he ranks 10th in expected wOBA. If there were a Statcast MVP race, Tucker would be in the running.

He's excelling in both contact and power hitting, at a level few other hitters are at this season. Tucker is one of only six hitters who are better than 95% of the league in both expected batting average and expected slugging.

Players in 95th+ percentile of MLB in both xBA and xSLG in 2021
Freddie Freeman (ATL) -- 100th in xBA, 97th in xSLG
Kyle Tucker (HOU) -- 99th in xBA, 97th in xSLG
Vladimir Guerrero Jr. (TOR) -- 98th in xBA, 98th in xSLG
Aaron Judge (NYY) -- 97th in xBA, 96th in xSLG
Bryce Harper (PHI) -- 97th in xBA, 100th in xSLG
Ronald Acuña Jr. (ATL) -- 95th in xBA, 99th in xSLG

Tucker's season trajectory goes to show you that if you keep squaring the ball up for long enough, your stat sheet should catch up eventually.

Let's rewind to the end of June. Three months into the season, Tucker's expected stats were already elite. He had a .313 xBA, .567 xSLG and .399 xwOBA. But he was only batting .268 and slugging .483, with a .342 wOBA. Those are huge "unlucky" gaps. In fact, the 57-point gap between his expected wOBA and actual wOBA was the second-largest among regular hitters. Tucker had the most hard-hit outs of any hitter in baseball.

Three months later, Tucker's 2021 expected stats look the same as they did before. But now the actual stats look like the expected stats. And Tucker looks like a star hitter.

The combination of speed, angle and frequency

The reason why Tucker's expected stats are so good is not complex. He's hitting the ball hard, he's hitting line drives and fly balls, and he's hitting both of those things a lot. If you hit a lot of hard line drives and fly balls, you should hit for average and power.

Forty-nine percent of the balls Tucker's hit this season, nearly half, have been hard-hit (that means 95 mph or harder off the bat). Forty-two percent of them have been in the launch angle "sweet spot" of 8-32 degrees (it's the sweet spot because it includes both line drives likely to be base hits and fly balls likely to be home runs or extra-base hits). And 26 percent of them have been both hard-hit and in the sweet spot.

All of those rates are excellent. Tucker is in the top 25 in MLB in hard-hit rate. He ranks third in sweet-spot rate. And he's in the top 10 in combined hard-hit/sweet-spot rate.

That covers the pure contact quality. But the real key for Tucker is that he's combining it with quantity. One in every five of his plate appearances ends with him hitting a ball that's both hard contact and sweet-spot contact. That's the best rate in the league.

Highest hard-hit + sweet-spot rate per PA in 2021
Of 171 hitters with 400 PA
1) Kyle Tucker (HOU): 19.4%
2) Nick Castellanos (CIN): 19.3%
3) Jesse Winker (CIN): 19.3%
4) Vladimir Guerrero Jr. (TOR): 18.0%
5) Joey Votto (CIN): 17.6%
Hard-hit + sweet-spot 95+ mph exit velocity and 8-32 degree launch angle

That is a leaderboard you want to be on top of.

Aggressive hitting

The approach at the plate that's producing such stellar contact is highly aggressive.

• He swings at 53% of all the pitches he sees, putting him just outside the most aggressive 10% of hitters in the Majors overall.

• He swings at the first pitch 43% of the time, fifth-most often among regular hitters, with five first-pitch home runs.

• He swings at 81% of pitches in the strike zone, making him one of only five regular hitters who swings at at least four of every five strikes.

• He swings at 95% of "meatballs" -- pitches that are middle-middle in the strike zone. That's the second-highest meatball swing rate in baseball.

Tucker attacks the ball, especially when it's in the strike zone. That last part is important. Squaring the ball up is a lot easier when you're swinging at strikes, even more so if they're perfect center-cut strikes.

Tucker is doing that, so he's squaring the ball up, so he's making great contact, so he's having a great second half and a great 2021 season.

So even though you might've seen more of the Astros' other stars than Tucker, you'll want to watch Tucker the rest of the way. He can be a playoff difference-maker.