The Necessary Analysis of a Red-Hot Nelson Cruz

Just as I was beginning to work this up, I got an email saying Nelson Cruz had been named the American League Player of the Week, which provides for a very convenient introductory sentence. Over the past seven days, Cruz has posted the highest wRC+ in baseball, by 85 points. Over the past seven days, Cruz has driven in 10 runs, while the Indians have driven in 11. Eight days ago, Cruz slugged a home run. Nine days ago, Cruz slugged a home run, and a couple of singles. All he’s hit have been singles and dingers, and he has almost as many dingers as singles. It’s been a good start for Nelson Cruz.

Which means analysis is obligatory. What’s gotten into Nelson Cruz? The answer is pretty much always “nothing sustainable,” but that’s never stopped us before. Nor does that mean there’s nothing to analyze. Cruz has been almost the entirety of the Mariners’ offense, and lately he’s been hotter than everyone else. Yet, how true is that? And is there anything else going on?

Obviously, there’s nothing sustainable about this many dingers. Obviously, there’s nothing sustainable about an .854 slugging percentage. Except for that one time, but baseball doesn’t really want us to remember and talk about that. This is all the clue you need: for his career, Cruz has basically an even number of doubles and homers. This year he has no doubles and eight homers. So, analysis complete! Nelson Cruz will cool off. I earn a salary for this.

There’s so much more that can be discussed. And why don’t I offer one point: this is the kind of hot streak we’ll understand very differently when we have more complete information. We’re already seeing hints of it. And we’ve had the ESPN Home Run Tracker available for a while. Classically, everything’s been bucketed. This was a single. This was an out. This was a home run! In the future, we’re going to talk more about quality of contact, and “deserved” outcomes. We’re closer than ever. And there’ll be a widening gap between the ballpark experience and the analytical experience.

Here’s what we know, that can’t be taken away: Nelson Cruz has eight home runs. They’ve all been home runs because they’ve flown beyond the outfield fence. Analysis is moving beyond buckets. The game will remain all about buckets. Games will always be about sequences of actual outcomes, instead of average or deserved outcomes. A strikeout will be the same as a line-out, in person.

But let’s take a look at the Home Run Tracker. I’d go with HITf/x data if it were more complete, but, it’s not. Shown on the front page of the Tracker: Cruz is the leader in “Just Enough” home runs. Just one of his home runs has a standard distance beyond 400 feet. He’s hit his home runs worse than he did a year ago. Based on the calculations, three homers would’ve left fewer than 10 ballparks, and five would’ve left fewer than 15. Just visually watching the homers, some of them have barely escaped. Some have really hung up there before coming down just a few feet too far.

Watch what happens! This is a little sloppy, but imagine we turn four of those home runs into fly outs. Long fly outs, but, fly outs. Suddenly, Cruz’s batting average is almost an exact match for his career mark. His on-base percentage is almost an exact match for his career mark. And his slugging percentage is almost an exact match for his career mark. Remember, it’s still terrifyingly early; it doesn’t take much tweaking to really mess the numbers up. By the familiar bucketing system, Cruz has been on a roll. And results-wise, he has been on a roll. But has he *really*? Has his performance been that much better? Or has he just had an extra few fly balls sneak out? The feel of recent Nelson Cruz is separate from the underlying reality of Nelson Cruz. The reality is that he makes a lot of hard contact. It’s his one tremendous strength. He hasn’t made unusually great contact; his contact has just led to unusually great results.

Maybe this is a simple or obvious point. It’s still a relevant point. It’s not that Cruz has been seeing the ball a million times better. It’s that he’s hit the ball hard, like usual, and sometimes that works out really great and sometimes that works out less great. There’ll be stretches where Cruz flies out to the track uncommonly often. Won’t mean he’s slumping.

There’s another thing here, though. Something I want to touch on, even though I don’t know what it means. Cruz, for his career, has hit 43% fly balls. His high mark is 46%, and lately he’s settled around 41%. This season, he’s at 64%, which is the highest fly-ball rate in the game through a few weeks. Still just 39 batted balls, but that was of sufficient interest to me to send me to some video. I decided to compare 2014 Nelson Cruz to 2015 Nelson Cruz, looking at home runs hit against very similar pitches. Below, you’re going to see three pairs. And for each swing, I’ve tried to calculate the angle of the bat below the horizontal.

Pair No. 1





Pair No. 2





Pair No. 3





All against similar pitches, you have differences of four, six, and eight degrees, as best as I could calculate them. In the 2015 examples, you’ve got Cruz swinging at a steeper angle than in the 2014 examples, and while those differences might seem small, I imagine there’s also a fairly small range we observe between extremes in the majors. It’s not like there are guys swinging with 0-degree angles and 90-degree angles. So Cruz has apparently swung with the barrel pointed more down, by some extent, and this would, if nothing else, fall in line with the increased fly-ball rate. It suggests more of an upward path through the zone, not that Cruz was ever hurting for home-run power.

The question in response would be: is it deliberate, or does this just happen sometimes? How consistent is a guy’s bat angle? All we see above are six examples split between two years. And I don’t even know what the error is in my angle calculations. It’s possible this might be the real takeaway. Cruz might be swinging a little steeper, for some reason. Or maybe he just has been swinging a little steeper, for some reason. I don’t know how “sticky” this is over time. I just know what I’ve seen, today. So for now I’ll just put it out there.

Cruz has been hugely productive. That much is true, and will forever be true, about the past week and a half. His performance, however, is a different story, seems like. Certainly not a bad story; just a different story. But there are hints of some sort of little tweak. It’s just too soon to say what it means. As far as hot streaks are concerned, Cruz slugged .748 last May. He slugged half that high in June. Adrian Gonzalez homered five times in his first 12 plate appearances. He’s homered zero times in his last 43. We all know how these things work. True talent moves around slowly. Results move around like a moth in a windstorm.

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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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Assuming he’s hitting the ball on the barrel in each, I think it would be better to measure hand height, since higher hands would result in steeper angles for a given pitch. This would remove the potential error from different pitches and camera angles.


I’m not sure where you would get the measurement of hand height being more accurate because you’d have the same issue with camera angles. But I suppose if Jeff took the pitch height from the PitchFx and estimated Cruz’s hand height from the GIFs you should still see some measurable difference.

I agree that if we had the proof of his hand height, that would be the best indicator of a possible change in approach.