This OAL Bobby Brown baseball was hit for a home run by Mark McGwire on May 31, 1987 against the NY Yankees. The game was held at Yankee Stadium and the pitcher was Tommy John. This was the 19th of McGwire's rookie record 49 homers during the 1987 season and the 22nd of his career. The ball was signed by McGwire during batting practice when the Athletics came to Yankee Stadium the following year. The blue ink full signature on the sweet spot, rates a 9. The provenance on this baseball is impeccable. The ball was caught by a man named John Foster, a die-hard Yankees fan. It was the first and only home run ball that he caught in the hundreds of baseball games that he attended. This is also the only autograph that Foster obtained from a non-Yankee. John Foster died earlier this year and our consignor obtained the ball directly from his widow, Diana. The ball is accompanied by a thorough letter of authenticity from Diana Foster that includes two pictures of the ball and its distinct markings. It also comes with a PSA/DNA letter confirming the authenticity of the autograph.