Welch was named to the AA All-Star team while playing for the Binghamton Mets.

[3] Welch made his major league debut on July 17, 1998, with the Phillies at age 25.

[4][5] On that day, the Phillies were playing against the Mets at Shea Stadium, with 23,298 people attending the game.

[5] Welch was called in to replace Desi Relaford, pitching and batting eighth in the bottom of the fifth inning.

His career ended abruptly when was diagnosed with a bone spur in his right elbow a week before starting the regular season with the Boston Red Sox, who he signed with after his time with the Phillies.