Carlos Zambrano’s Lower Arm Slot: cause for concern?

I recently wrote an article on Jonathan Papelbon’s arm slot issues. My conclusion:

“I don’t know if Papelbon’s shoulder is bothering him or not. There’s no way for me to know for sure. All I’m trying to point out here is that he is showing some of the signs of a guy who might be struggling with his shoulder.”

I had originally intended to write an article in which I discussed both Papelbon and Carlos Zambrano. The Papelbon article ran longer than I anticipated, so I split them up. Nonetheless, I and many others have been noticing the same issues with Zambrano.

Take Carrie Muskat’s recent Mailbag Q&A, for example:

I saw a feature about how Carlos Zambrano’s arm slot is down this year, and he’s finishing across his body instead of toward the plate. It made me wonder, how much film does pitching coach Larry Rothschild watch on pitchers when they’re struggling, and, assuming they figure out what is going wrong, how do you even go about trying to get a pitcher to go back to throwing from the same position they used to?”

“Rothschild watches video constantly. He has a library of DVDs with each player’s games. He is well aware of Zambrano’s arm slot issues, and so is Zambrano.The problem is, once Big Z takes the mound, he reverts to his old ways. He admitted in his last start that he realized what he was doing wrong during an at-bat to Washington’s Ryan Zimmerman, and was able to correct it.”

In case you’re not convinced of Z’s arm slot issues, here’s some video comparing Zambrano in ’05 to ’07:

Both of these pitches are sinkers away to lefties that resulted in strikeouts.

All the indications of a lower slot are there.

1) At around the fifth frame, notice how his torso is tilted (towards the right) a little more in ’07:

2) At release, his shoulder plane is flatter in ’07. A few frames after release his arm has finished higher, indicating a flatter arm path consistent with a lower slot. In the following image, I drew angles to show it. The two points I linked represent where his fingers are at release and where his hand ends up three frames after release:


The spin he imparts on these pitches are different. His current sinker has a more sideways tilt to it (think roughly 2:30 to 8:30 on a clock from the center field view). His sinker used to have less lateral movement, but with later, harder, sharper “run”(into a righthanded hitter) and sink. Batters are more likely to describe the ’05 sinker as the “heavier” sinker, and it should generate more ground balls.

3) Also note on the picture above (after release) how his back shoulder in ’05 has gone farther forward (towards the plate) and down, indicating that he’s put better effort “through the ball” instead of “swiping the ball.” I hate the term “bending the back,” but watch how in ’05 his back is more parallel to the ground. That is indicative of a more north-south application of force.

What I just don’t get

I assume, as Muskat’s article suggests, that Rothschild has addressed the arm slot issue and Big Z is fully aware of it. Here’s a few of my concerns:

Trust me, a great majority of us pitchers want to know how hard we are throwing. Because I had been a soft-tosser for most of my career, one of my proudest moments in baseball was when I looked up at the scoreboard in Brockton and saw “PITCH SPEED= 90 mph.” Zambrano seems like a pitcher who pays attention to the radar gun. Young, aggressive pitchers like to throw hard, show off their velocity and strike people out. In all the video that I’ve seen of Zambrano, his drop in velocity this year is evident. If Z knows that he throws harder from a higher slot, why won’t he make his arm get there? Is he subconsciously protecting his shoulder?

A Hardball Times Update
Goodbye for now.

Let me quickly explain “protecting the shoulder.”
Again, I’ll borrow a line from my Jonathan Papelbon article.

“One of the clearest indications of a pitcher who is struggling with shoulder soreness/pain is a drop in his arm slot. From a personal standpoint, I know that (when I threw overhand) when my shoulder was hurting me, I would tend to lower my elbow in order to “protect the shoulder.” While I’m not totally sure of the cause/effect, I DO know that since becoming a sidearmer/submariner, I have had significantly less issues with shoulder pain. Consider this analogy: Have you ever gone to the gym for a workout and REALLY worked on your shoulders? How do they feel the next day? Do you have trouble raising your arms and getting your elbows above your shoulder plane? Yeah, me too. Sort of the same idea here except that pitchers are dealing more with ligament pain instead of muscular soreness.”

Consider this clip…….

The pitch on the left in ’05 is not a sinker. It is (I assume, due to his much higher slot) a four-seam fastball with minimal lateral movement. His four-seam fastball is a strikeout/pop up type pitch. A pitcher wants hitters to swing over his sinker and under his four-seamer. The ’05 pitch in clip two above is a “high, hard one.” I see Zambrano throwing fewer pitches like this nowadays.

Is Zambrano so enamored with the movement he gets with a lower slot that he prefers to not throw harder? Has Zambrano been instructed to pitch to contact in order to reduce his pitch count? Are we to believe that Zambrano has matured so much as pitcher that he prefers to “take a little off” instead of trying to throw it by the hitter?

I’m quite certain that Rothschild has tried to convince Zambrano that he needs to “stay on top of the ball” and “drive down through it.” He can point to 2005 and his higher ground ball and strikeout rates. He can also mention his lower walk and home run rates as to why to go with a slightly higher slot. Why hasn’t he been able to make the adjustment? These questions (which I don’t have the answer to) make me wonder whether there’s a health-related issue we haven’t heard about.

Final Thoughts

As I stated above, a clear indication of a pitcher who is favoring his shoulder is a pitcher who lowers his arm slot. The Zambrano video, however, is messing with me. What you don’t want to see is a pitcher lowering his elbow well below his shoulder plane. Since Zambrano is tilting his torso forward in the ’07 clips above, it is difficult to discern (on video) whether the lower arm slot is a result of Big Z lowering his elbow relative to his shoulder plane (which is bad, health-wise) or if it is a result of him tilting his torso more (not bad). I think I can see some evidence of how the ’07 Zambrano seems to be “pushing” the ball more than his ’05 counterpart. Check the shoulder plane/elbow height relationship a few frames before release…

Not really conclusive, but there’s just something there.
I’d also like to point out that I’ve watched plenty of 2006 Zambrano video. Without going into much detail, I’d estimate that Zambrano’s arm slot was slightly lower last year than in 2005 but still higher than in 2007. Could the gradual lowering of his arm slot (and extra movement he can’t control from the lower slot) be the reason for a spike in his walk rate? I don’t know… just throwing it out there.

Zambrano has been asking for a lucrative contract extension. Considering his performance so far this year, his velocity loss and possible signs of arm trouble, the Cubs would be foolish to sign him to a long-term deal. Too many question marks there. I sincerely hope that what I’m seeing is not what I think I’m seeing.

Good luck Z.

POSTSCRIPT: May 15th, 2007: Cubs at Mets:

I wanted to add this short review of his latest start. On this particular day, it did look like Zambrano has raised his arm slot a bit. However, something just didn’t look right, regardless of the results of that game. An interesting exchange occurred in the first inning of that game. The first pitch to Endy Chavez was an 88 mph fastball that he took for a strike. The expression on my face probably said “uggghhh, what was that?” Sure, it was more over the top but he looked stiff, really stiff.

Keith Hernandez, almost reading my mind, then said, “Is Zambrano throwing like he has a sore arm or something?” His sidekick agreed, “I know, he is just so short-arming it.”

That short half-inning, in which the Mets’ broadcasters discussed Zambrano’s mechanics, further reinforced my concerns. Something is just not right.


Comments are closed.