[1] Gilbert played professional baseball in the Red Sox and Mets minor league systems before entering the life insurance business at age 24.
[2][3] When a friend of his who was a baseball agent died unexpectedly, Gilbert took over representation for some of his clients.
[5] Gilbert represented numerous star players that signed some of the most lucrative contracts in professional sports in the 1980s and 1990s, including Barry Bonds, Bobby Bonilla, Jose Canseco, George Brett, Bret Saberhagen and Danny Tartabull.
[6] Gilbert sold his share of the agency to his partners in January 1999, retiring from the sports agent business at the age of 51.
[7] In November 2000, Gilbert joined the Chicago White Sox as a special assistant to owner and chairman Jerry Reinsdorf.