This morning my friend AK from The Bat Shatters pointed out a great video by the New York Times on Mariano Rivera’s cutter.  It may be old news to some of you, but I want to wholeheartedly recommend it anyway.  It gives you a batters-eye view of what Rivera’s cutter looks like as it approaches the plate and you can get an idea of what “late movement” actually looks like.  Starting at 1:45 they also do some very fancy stuff grouping together all of his pitches thrown in 2009 and showing how they came in to left-handed and right-handed batters.  Here’s the link for the video, check it out. A related question: if you crouched down behind home-plate and he threw one cutter to you at full speed, with no practice catches, what would be the odds that you could actually catch it?  I’m giving myself no more than 10% odds.

Joel Sherman has a new piece in his Hardball Blog where he discusses Mariano Rivera’s pending free agency with the Great One himself. Here’s what was said:

When I asked Rivera what he wanted, the great righty said, “During the season it is hard to focus on the contract. During the season, I have to do what is right by the team.”

When I asked if he would be amenable to doing what Andy Pettitte (another free-agent-to-be) does, and take one-year contracts and determine at the end of each season if he wants to continue to play, Rivera said, “Something like that would be fine.”

In the past, however, Rivera has been pretty rigid about wanting top-of-the-market money for multiple years.

I take that last sentence that Joel wrote more seriously than anything Mariano says at this point. I think he made it clear he didn’t really want to get into it, and was just being agreeable to move things along. Also, Mariano has a history of being very amenable during the season, and very difficult after. In Mariano’s last contract negotiation everything was smooth early in the process, but then things got very bumpy as the off season progressed. He filed for Free Agency (unlike Posada) even though he had no other suitors, and was clearly annoyed with the Yanks when they wouldn’t go for the extra year and $ he wanted. Brian Cashman has stated that Mo has never left a dime on the table in these negotiations, and once his agent gets in his ear his tune may quickly change. Further, Andy Pettitte often spoke last year about ‘what a horrible negotiator’ he was for making it clear he would only play for the Yanks, resulting in a low base/ incentive-laden deal for that season. But at age 40, he may not want to have the obligation of a multi-year deal, opting to take things one year at a time. At some point he will lose his effectiveness, and he’s not the type of pitcher who will want to go out there and embarrass himself. I’ll go 50-50 on this one, but again I have my doubts.

On Wednesday, Moshe pointed us to an article on Rational Pastime called “Mariano Watch: April” which detailed in glorious fashion the interesting phenomenon surrounding Mariano’s cutter.  The piece first began by showing that Mariano’s fastball velocity is down when compared to this time last year.  As you can see in the chart below (courtesy of Rational Pastime), he’s ranging between 0.2 and 0.6 mph slower on the cutter so far.

Fangraphs confirms that his velocity has been on a downward track since 2007, but this isn’t really news to Yankees fans.  J-Doug wonders, as have many analysts, why Rivera’s effectiveness hasn’t decreased along with his velocity.  He plots the average break on Rivera’s cutter, using all kinds of fancy math, and notes that the cutter is breaking a full inch more in 2010 than it is in 2009.  To wit:

So why I am bringing this up again?  Well, a few months ago Moshe tweeted that a source, which was me, passed along some insider information about Rivera and his approach to his cutter.  Rivera wasn’t concerned about the drop in velocity, and the reason was the he had noticed that he was able to generate more break on the cutter when it was thrown slower.  Now, from a physics perspective, I’m not exactly sure why it works like this.  Is it simply a matter of it taking slightly longer to get to the plate, and having a longer time to “spin”? Or does the velocity affect the break of the cutter in a different, more fundamental way? Does throwing it 3-4 mph faster make it straighter?  Can anyone explain Mariano Rivera and his ability to defy aging?

When I originally heard this information about his cutter, I thought it was cool and interesting but maybe just a tad bit apocryphal.  It sounded like the kind of story you hear a hundred times over in Spring Training: Player X lost 20 pounds, Player Y learned a changeup (ahem, Hughes), Player Z got LASIK.  Far be it from me to doubt the great Mariano Rivera, but I wasn’t absolutely certain that the Pitch F(x) data would back up his claims.  But Rivera was right.

There is, quite obviously, an uneasy tension between the more stats-oriented fanbase and the “scouting” fanbase, if I could use two very general and inaccurate terms.  I enjoy participating in the mocking of the stories like the ones I listed above.  I’m skeptical of any story written about how a player got a new workout routine and seems poised for a breakout year, unless it’s based on firm statistical analysis.  There’s a good reason for this: most of the stories turn out to be nothing more than filler that helps pass away the interminable days of PFP and intersquad matchups in March.  But beyond that, and I’m certain that I’m not the first to suggest this, maybe there is room for a little “mystery” when it comes to approaching this game.  In this case, the narrative of Mariano’s cutter preceded my ability to verify or validate it, but it was true nevertheless.  I like this.  And I like that people smarter than me are able to prove Rivera, who was just going on his sight and his feel, correct.  There’s a lot of tension, even dislike, between the camps of stats vs. scouting, new vs. old, proof vs. feel, etc.  A lot of times there doesn’t seem to be too much respect or open-mindedness in the conversation.  In this case, I appreciate that the two don’t need to be mutually exclusive.  Mystery and hard science can live next to each other, one validating the other.  And who better to embody it, to stand in the middle, than the great Mariano Rivera?