Why are the Yankees the only Major League baseball team that requires all players to shave clean? - Quora
Don Mattingly Refuses Hair Cut, Gets Ovation After Benching! New York Yankees
Yankees great Don Mattingly once spoke about his main gripe with his infamous haircut benching saga
Legendary mustache-haver Don Mattingly bans facial hair on Marlins
Mattingly removes no facial hair policy
Who has a mustache on the Yankees? Why Matt Carpenter's facial hair doesn't violate team rules
The story behind the Yankees' facial hair policy - Pinstripe Alley
Yankees need to end outdated facial hair policy
Apple TV bringing the facts for this AL East clash tonight : r/baseball
Don Mattingly's cool with players growing out their hair, but he won't bring back his 'stache