Lightly soiled and game prepared A.Selig MLB baseball with Yankees 100th anniversary stampings as used in Roger Clemens historic 300th career victory and 4,000th career strikeout. The ball shows evident "mudding" for game preparation and some additional evidence of game use. Signed by Clemens in blue ink across the sweet spot adding "300Ws/4,000Ks" inscription. The ball was obtained during the game by Yankees teammate Jason Anderson who had Clemens sign and inscribe the baseball. Includes full LOA from PSA/DNA (autograph/inscription) and signed letter of provenance from Jason Anderson (ball and signature): Ball: EX, Signature: NM-MT