Francisco Rodriguez Says 'It's Rosin'

Yesterday I posed the question "Does Francisco Rodriguez Doctor the Baseball?" after an analysis surfaced suggesting that he was using a substance. In the same story I was skeptical about the rumor because there was a lack of variation in the velocity of Franky's pitches. If K-Rod were using the white substance under the brim of his hat to doctor the ball, you would have expected to see a drop in pitch velocity the times he reached for his cap, since he would have been throwing off-speed pitches in those instances. Well thanks to Matt Hurst's Riverside Press-Enterprise Baseball Blog, we have an answer from Francisco himself, which is in accordance with what commenter George B Vieto suggested:

I talked to Francisco Rodriguez about this white substance on the underside of his bill and he grabbed the hat from his locker, flipped it over and said "This?"
On the black underside of his cap was a sizable white smudge.
"It's rosin," Rodriguez said.
There is a rosin bag on the back of every mound in professional baseball filled with the white, chalky substance that pitcher's can use on their hands to eliminate sweat so they can better grip the ball. John Lackey, for instance, puts it on his left wrist, just above his glove, so he can wipe his right hand on the wrist instead of constantly going to the rosin bag.
So, why does Rodriguez continually tug on his cap, bringing suspicion about?
Because he stopped wearing his trademark goggles, he fidgets with his hat instead of his glasses.

Well that answers the question from Franky's end. Hurst still notes that Major League Baseball is looking into the matter.

On a related note, I watched K-Rod throw the ninth inning of last night's loss to the A's in which Rodriguez gave up the game-winning home run to Mike Piazza, and I witnessed the exact same behavior; Franky repeatedly wiped his hand on his pants, and thumbed the bill of his cap, and in most instances wound up throwing a fastball. I also noticed the white smudge on his cap, but it seemed to be just a rosin stain that is starting to wear in more on the hat. Since the photos above were taken on Opening Day, it's possible that Franky hadn't worked the rosin into his hat just yet (most players usually start the season with fresh gear), just like a batter who wears pine tar on his helmet. At the beginning of the season the helmet is shiny, by mid-season it's dull and worn out. That's probably what the case was here.

The man who first noticed the substance under Franky's brim, Derek Zumsteg, has since responded on his blog by citing MLB rules against players using any foreign substance. While the legitimacy of those rules cannot be denied, the enforcement of them would change the game of baseball, considering a rosin bag sits at the back of every mound, and rags of pine tar sit in every dugout (and both foreign substances are used by most players).

Previously at FanHouse:
Does Francisco Rodriguez Doctor the Baseball?