When Biff Henderson is around, you can guess you're in for a laugh.

The Late Show with David Letterman regular traveled to Florida to join the Yankees for spring training and spent the day joking with stars such as Mariano Rivera, Alex Rodriguez and Derek Jeter.

He also got to pal around with former Yankees David Wells and Reggie Jackson, going so far as to stump Mr. October with an impossible request. See more in the video below.