Sunday night, Rafael Devers went yard against Aroldis Chapman, even though Chapman’s fastball was recorded at nearly 103 miles per hour. It’s the fastest pitch hit out in the pitch-tracking era, which has spanned nearly a decade, and that linked article was almost obligatory. Had to write something up. Devers tagged Chapman, even though it seemed like Chapman had his best stuff.

To a certain extent, you can’t blame Chapman for what happened. He threw a lefty-on-lefty fastball, with two strikes, kind of up and in at over 100 miles per hour. That pitch should basically never go for a homer. I’m still not sure how it happened. But, ignore the homer for a moment. Pretend it was a double, or a single. Or even an out! Whatever you like. Devers made contact. Solid contact, at that. The contact is what’s strange, and there are signs of a problematic trend, here.

Let’s examine Chapman’s career, shall we? I’ve prepared three rolling-average plots, each using samples of 30 games. This first one shows the development of Chapman’s average fastball.

You could argue there’s a recent down tick, but Chapman is still regularly reaching triple digits. His fastball is fast. Still a Chapman fastball. Like we all saw with the at-bat against Devers, Chapman can still run it up there about as hard as he ever has. So, based on the velocity, Chapman seems okay. Shifting to pitch location, we can see a trend from the past year and a half or so.

Chapman has been aggressive with pitching in the zone. He’s thrown two-thirds of his pitches for strikes, and this year in particular, he’s regularly gotten ahead with the first pitches of plate appearances. And, of course, with such an unhittable fastball, why mess around? Chapman had a terrific 2016, in which he came right after his opponents. This year, he’s done much of the same. But-

That plot shows contact rate. Chapman’s present contact rate is far higher than it’s been since earlier in 2013. All of a sudden — it’s not so much that Chapman is hittable, but he’s a great deal more hittable than he’s been. Look at this table of the biggest contact-rate declines from last year, with a minimum of 30 innings:

Chapman has a contact rate of 75.2%. The league-average reliever has a contact rate of 75.4%. No pitcher’s contact rate has dropped by more, and although Chapman is still mostly okay, and although this could be a blip, he was on the disabled list for a month, with a rotator-cuff problem. His contact rate has only risen since he came back. The velocity is there, and maybe that’s the most important thing, but you do have to wonder. Chapman’s been one of the most dominant relievers anyone’s ever seen. Real cracks appear to be forming.

Related to this, consider Chapman’s year-to-year ranks among all relievers in Win Probability Added:

• 2011: 24th
• 2012: 8th
• 2013: 44th
• 2014: 15th
• 2015: 16th
• 2016: 7th
• 2017: 337th

I don’t know what the issue is. It wouldn’t be a surprise at all if it were linked to the injury. In that case, it would be nice to have an explanation. But even then, explanation isn’t resolution. Aroldis Chapman is allowing roughly league-average contact. He’s in the first year of the largest contract a reliever has ever signed.

I don’t think many people expected the NL Central to be very close, but here we are, with four teams within four games of the divisional lead. Although the Cubs, as expected, have risen to sit in first, their closest rivals now are the Cardinals, but one single game behind. For those Cardinals, it’s been a pretty ordinary season, and it’s been a pretty weird one.

The best player on the Cardinals, by Wins Above Replacement, leads the team by a margin of one full win. The best player on the Cardinals didn’t crack the opening-day roster. As a consequence of that, the best player on the Cardinals gave serious thought to calling it quits. The best player on the Cardinals is a 29-year-old who came into the year with a half-season’s worth of major-league experience. The best player on the Cardinals has himself an extended injury history, and the best player on the Cardinals has also had to manage a degenerative eye condition, called keratoconus. The best player on the Cardinals probably isn’t supposed to be the best player on the Cardinals.

And still, at least statistically, the best player on the Cardinals has been Tommy Pham. It’s been fun for me to watch Mike Trout glide up the WAR leaderboard since his return to the bigs. As I write this, he’s tied with Paul Goldschmidt for third place, as hitters go. Pham is no Trout — he’s down there in 22nd, among position players. But that’s 22nd out of a sample a lot bigger than 22 players. That’s 22nd even though Pham hasn’t been up all year. That’s 22nd, which puts Pham above guys like Michael Conforto, Travis Shaw, and Andrew McCutchen.

Watch Tommy Pham hit a dinger. I don’t know what purpose this clip serves, but, who doesn’t want to watch a dinger? It’s a visual break from the wall of text.

Pham’s personal story is far too deep, complex, and interesting for a short blog post. I’d recommend reading this feature, or this one, or this one. Pham’s dealt with adversity from nearly the start of his life, and that’s for reasons even beyond his compromised vision. But just from a baseball perspective: Can you imagine trying to hit with compromised vision? This is an excerpt from the first of those links.

Pham said he is legally blind in his left eye due to keratoconus.

At present, Pham is able to play and perform through careful management of special contact lenses. I’ve already mentioned that Pham looks excellent according to WAR. He’s gotten there by being an all-around contributor. This is the kind of thing I’ve called attention to before when talking about Anthony Rendon. I looked at a spreadsheet of this year’s players with at least 250 plate appearances. I narrowed the pool down to only those players who’ve been at least average by K-BB%, ISO, BABIP, baserunning, and defense. The group includes only nine players. Rendon, yeah. Pham, too. Pham’s been solid across the board. He’s even cleaned up his biggest on-field weakness.

This right here is probably the highlight of this entry. We’ve got some plate-discipline data stretching back more than a decade and a half. I looked at every single player over that span to bat at least 100 times in consecutive seasons. Here are the 10 biggest year-to-year improvements in contact rate:

That’s a hard thing to pull off by accident. As a result, Pham has trimmed his strikeout rate by an unbelievable 15 percentage points, and although Pham now just looks pretty similar to what he was as a part-time player in 2015, he’s doing it now over greater playing time. And so Pham is now a player with a career WAR/600 of 4.5.

The St. Louis outfield remains crowded. Pham remains an objectively risky player, or at least a player with a higher degree of volatility. I don’t know to what extent the Cardinals actually trust him, but that trust has to be a lot stronger than it was a few months ago, and, if it weren’t for Pham, the Cardinals wouldn’t be where they are today in the standings. The best player on the Cardinals is a miracle. I don’t think I’m even exaggerating.