Dave Jacobs was Sugar Ray Leonard's first trainer as an amateur. After Leonard turned professional in 1977, Jacobs worked for him as an assistant trainer.
After Leonard lost to Roberto Duran in 1980, Jacobs resigned because he didn't agree with Leonard's decision to have an immediate rematch with Duran. Jacobs rejoined Leonard when he came back to fight Marvin Hagler in 1987, but he was let go after Leonard's controversial draw with Thomas Hearns in 1989.
Jacobs currently trains fighters at the Sugar Ray Leonard Boxing Center in Palmer Park, Maryland.