Let’s Watch Aroldis Chapman and Javier Baez

Prospects are babies. They’re eagerly anticipated, they’re evaluated by their ceilings, their arrivals are memorable and frequently painful, and these days they’re traded for goods less than ever. They continue to be interesting for a handful of months, but then they start to develop into more fully-formed people, and the magic of limitless possibility disintegrates. Sometimes they turn into remarkable things, more often they turn into unremarkable things, and regardless, it doesn’t take long before they’re taken for granted. Toward the beginning, everything is celebrated. Later on, mistakes aren’t so novel, they aren’t so easy to explain away.

Javier Baez still counts as a prospect, even though his big-league career is weeks underway. He’s among the most exciting prospects we’ve seen in baseball in some years, and though it’s a certainty that he’ll be less compelling a year or two from now, at the moment everything he’s involved in can be turned into a highlight. If he were a real baby, all his activity would be posted on Facebook. Some people might already be getting Baez fatigue, but I’m not one of them, and even if I were, I’d probably make an exception for a showdown between Baez and a similarly extreme sort of pitcher. A pitcher like, I don’t know, Aroldis Chapman. Who Baez faced for the first time on Wednesday night in the top of the ninth of a close game.

Earlier this season, people paid a lot of attention to an at-bat between Kenley Jansen and Miguel Cabrera. It was compelling, because both Jansen and Cabrera are extremely talented. Chapman vs. Baez is compelling because both players are extremely powerful. There’s no one who throws harder than Aroldis Chapman. There might be no one who swings harder than Javier Baez.Who wouldn’t want to watch them go head-to-head over and over? They haven’t yet gone head-to-head over and over, but they have gone head-to-head once. Let’s put that at-bat under the microscope.

The setting: 7-5 Reds, top of the ninth. The Cubs haven’t been in the race for a while, and the Reds aren’t really in the race anymore, but a win is a win and the game’s stakes were at their highest. Baez came to bat against Chapman with two on and two out. Through August 15, Chapman had struck out 52% of the batters he’d seen. Then he had that four-walk meltdown in Colorado, accompanied by a little shoulder discomfort. He came back to strike out 11 of 17 batters, leading up to Baez. Chapman, it seemed, was back to normal. There was no reason to believe Baez wasn’t normal.

A walk set up the showdown, with Baez standing in as the go-ahead run. Let’s go back and forth between this post and the two TV broadcasts. Representing the Cubs: Len Kasper and Jim Deshaies. Representing the Reds: Thom Brennaman and Chris Welsh. They both had things to say as Baez approached from the on-deck area.

Kasper: This is fun. Javier Baez against Aroldis Chapman. The hardest thrower in the league against the hardest swinger.

Deshaies: He gets the head out in front of one of these fastballs, it might go 490 feet.

Kasper: It kind of feels like there are two choices here. Of all the things that can happen in an at-bat, signs seem to point to two possible outcomes. I don’t even have to say what they are. [Deshaies laughs] So here we go!

The other side:

Welsh: Now [Bryan Price]’s got a dangerous hitter up there, but really a compelling matchup that, if you like baseball, you’re looking forward to seeing this. Javier Baez, uber-prospect, and the hardest thrower in the major leagues in Aroldis Chapman, squaring off, game on the line.

Brennaman: So here we go.

You’ll notice a repeat line: “so here we go”, like they’re about to get onto a carnival ride. Which isn’t inaccurate, but Kasper said it like a man who takes a lot of pleasure in going on carnival rides. Brennaman came off a little more nervous, a little more cautious. Brennaman came off like a man who’d spent the ten minutes in line reading on his phone about instances of people getting crippled or killed on ill-fated carnival rides.

Baez stepped in. Chapman threw a fastball.


101 miles per hour. Taken, down the gut.

Deshaies: That’s where you have your best chance against Chapman, is if you get one of those fastballs down a little bit. When it’s up above the hands, it’s really tough to get to.

Nothing incorrect about that. Better to hit a lower Chapman fastball than a higher Chapman fastball. Unfortunately, there’s no going back and repeating the fastball, for Baez. You could call it a missed opportunity, I suppose. The Reds’ broadcast essentially did.

Brennaman: I am stunned he took that pitch.

Welsh: Yeah. Maybe he wanted to see what 101 looked like. Or sounded like.

“Stunned”? Was Thom Brennaman really stunned that Javier Baez took a first-pitch 101 mile-per-hour fastball? I understand the pitch was in a hittable location, if such a location even exists with Aroldis Chapman, but think about what Brennaman is suggesting. Chapman throws the hardest fastballs in the game. Javier Baez had never stood in against him before. He’s seen the highlight shows, and he’s seen Chapman from the dugout and the on-deck circle, but Baez had never before had one of those fastballs fly a few feet from his head. He didn’t know what the ball looked like out of Chapman’s hand. He didn’t know Chapman’s delivery or timing. You don’t want to be too passive, and you always want to go up to the plate ready to hit, but is it really stunning that a rookie hitter took the first pitch from Aroldis Chapman he’d ever seen in his life? Listen to Chris, Thom.

The second pitch wasn’t a fastball.


We all recognize that as unfair, but it’s not uniquely unfair to Baez — Chapman is just unfair across the board. The response from the Cubs’ broadcast:

Kasper: [complete silence]

Deshaies: [complete silence]

I mean, what do you say to that? Baez had seen one pitch from Chapman, and it was 101 miles per hour, and it was a fastball. So he got all geared up to hit a pitch at that velocity, and then Chapman subtracted 11 ticks, and dropped a breaking ball just below the zone. This was, for all intents and purposes, an unhittable pitch, and don’t make too much of Baez being ahead of it — that was practically inevitable. And with the slider in that location, almost anyone would’ve swung.


Brennaman: That’s a slider at 90. You’re not seeing that down at Double-A.

Welsh: You know, that might be one of the best sliders I’ve ever seen him throw. I mean, the bottom dropped out of that bad boy.

Baez was behind Chapman 0-and-2. He’d seen one unparalleled fastball, and one perfect slider with fastball velocity. Coming into the at-bat, Baez had fallen behind 0-and-2 27 times, with 20 subsequent strikeouts. Chapman had gotten ahead 0-and-2 46 times, with 34 subsequent strikeouts. There was an air of inevitability. Chapman came with a fastball, harder than the first.


102 miles per hour. Contact. Interestingly, Devin Mesoraco wanted the pitch down, even though Baez has demonstrated a vulnerability to high heat. Chapman threw the pitch up anyway, but not enough up, staying within the strike zone. This time, Baez was ready for the best heat he’d ever seen. It just took him a pitch to find his timing. One notes that, while Baez’s contact rate out of the zone is lousy, his contact rate within the zone is practically average, and that’s not a product of him cutting down his swing.

Off the bat, Chapman got that feeling he seldom feels.


Look at Chapman. Look at the faces in the seats. Look at the situation and the velocity reading. In Chapman’s mind, the outcome was already decided. He knows exactly how much power he supplies, and he’d probably heard something about Baez at some point in the lead-up.

“I had to take a couple of steps back, and I got a little scared; it sounded so loud and it was really high, but, the ball jumps off his bat no matter where he hits it to,” Reds center fielder Billy Hamilton said.

“It sounded good,” [Rick] Renteria said.

In the end:


In just about dead center field, Hamilton tracked the ball down a couple feet shy of the fence. Baez had hit the ball far enough to knock a home run to most areas. He just didn’t hit the ball far enough to knock a home run to the area he hit the ball to, and so Chapman picked up what the box score indicates was an only somewhat troubling save. The relief was immediately apparent on Hamilton’s face:


It was immediately apparent on Chapman’s face:


Luck, was all that was, and the Reds weren’t about to deny it. There’s a negligible difference between that fly ball and a lead-changing home run. The Reds just got the break in their favor, justifying Brennaman’s earlier uneasy tone. The ride, for Cincinnati, came ever so close to disaster. For Chicago, there was no longer-term payoff, but they were just in it for the fun, and fun’s what they got through to the final instant. Life’s not so serious when you broadcast for a sub-.500 baseball team. Entertainment’s entertainment, and broadcasters of other teams can get nervous about potential consequences.

From Baseball Savant, here’s the hit chart for every pitch Chapman has ever thrown at least 102 miles per hour:


You can spot the Baez drive. Out of 74 swing attempts, 36% have whiffed. Just 22% have been hit into play, and only two balls ever have been hit pretty deep. Baez’s is the deepest. It came just shy of being deep enough, but all that is is half a millimeter or a wind gust. Javier Baez didn’t get the best of Aroldis Chapman, but, he basically did. You could argue that nobody won. You could argue that nobody lost.

Len Kasper said it felt like there were two choices. The at-bat was all but certain to end with a home run or a strikeout. His broadcast partner laughed, as if to say, “you’re exaggerating, but really, you’re probably not.”

We hoped you liked reading Let’s Watch Aroldis Chapman and Javier Baez by Jeff Sullivan!

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Jeff made Lookout Landing a thing, but he does not still write there about the Mariners. He does write here, sometimes about the Mariners, but usually not.

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If they batted against each other for 100 ABs, how many strikeouts would results? 60? 65?


I’m sure there is a diminishing effect on how high a strikeout total can actually get, but Chapman has struck out 85 of his 164 total batters faced (51.8 K%). That’s the average against all batters. Baez is easily leading the majors in K% with at least 90 PAs at 43.2 K%. I’d assume it would have to be a K% of 65 at least.


But you would have to also assume Baez would cut his K% if he repeatedly faced the same pitcher in 100 consecutive ABs.


Baez have gotten worse in the last 2 weeks. At the moment he might reach 100k in 48 games, shattering the record set by Reynolds of 68 games. That is a smashing record

I know the power tool is their but his slugging % in the last 12 days is 370 that is just better then revere and Hamilton’s for the year

Josh G
Josh G

Why would you pick a number that is greater than either of their K%?

Chris B
Chris B

Because that’s what makes sense. Baez has struck out 43% of the time against essentially a random sampling of pitchers. Pit him against an elite strikeout artist like Chapman, and that number probably goes up significantly. Chapman has struck out 51% of all hitters he has faced. Pit him against a guy who K’s a ton, and that number probably goes up significantly.

Put a great team with a .600 winning percentage against a terrible team with a .400 winning percentage in a 100 game series. It stands to reason the good team would win more than 60 of those games. Same concept.

Chris B
Chris B

In fact, using the quick and dirty method in this articl, that .600 team should win about 70 games. Obviously this method doesn’t apply to K% but it’s sort of the same principle.

Chris B
Chris B