I sat in the front row of the left field bleachers a few nights ago at the Giants game vs. the Mets. The Mets left fielder was Jason Bay, and he was wearing that special uniform number, 44. Forty four is a special number because of the hall of fame sluggers that have worn it in the past. Hank Aaron wore it and was a great young player. Willie McCovey, being from the same hometown of Mobile, Alabama, wore it when he broke in with the Giants because Aaron was his idol. McCovey was a rookie in 1959, five years after Aaron. Later, in the 70's, Reggie Jackson adopted the number when he signed with the Yankees. He kept it with the Angels and during his last year back with the A's.
Forty four is one of those hallowed numbers that players respect. Players know who has worn it in the past. So when a player takes 44, he's treading on ground that demands something from him. He needs to turn out to be a superstar.
So, the heckling line is this: "Hey, 44, who do you think you are? There's Hank Aaron, Willie McCovey, Reggie Jackson, and you?"
Jason Bay heard it from a #44 apologist.