10 Apr 1999
Irene Pacheco beats Luis Cox Coronado via knockout 9/12
Flyweight (112 lb)
Irene Pacheco becomes the IBF Flyweight world champion
16 Oct 1999
Irene Pacheco beats Ferid Ben Jeddou via knockout 4/12
14 Jan 2000
Irene Pacheco beats Pedro Pena via knockout 11/12
10 Nov 2000
Irene Pacheco beats Masibulele Makepula via majority decision 12/12
9 Nov 2001
Irene Pacheco beats Mike Trejo via knockout 4/12
29 Nov 2002
Irene Pacheco beats Alejandro Montiel via unanimous decision 12/12
27 Sep 2003
Irene Pacheco beats Damaen Kelly via knockout 7/12
16 Dec 2004
Vic Darchinyan beats Irene Pacheco via knockout 11/12
30 Mar 2007
Jhonny Gonzalez beats Irene Pacheco via knockout 9/12
Bantamweight (118 lb)