Here are well known boxers who went on to win world titles in the professional game and are considered great, the ones I have starred have the potential to be great:

~ Floyd Patterson (U.S.A.)- won the gold medal in the middleweight division at the 1952 Olympics and held the world heavyweight title from 11/30/1956 to 6/26/1959, and again from 6/20/1960 to 9/25/1962. He was also the first fighter to ever regain the heavyweight title.

~ Cassius Clay later known as Muhammad Ali (U.S.A.)- won the gold medal in the light heavyweight division at the 1960 Olympics and held the world heavyweight title from 2/25/1964 to 3/22/1967, again from 10/30/1974 to 2/15/1978, and again from 9/15/1978 to when he retired the following year. He was also the first fighter to ever win the heavyweight title 3 times.

~ Joe Frazier (U.S.A.)- won the gold medal in the heavyweight division at the 1964 Olympics and held the world heavyweight title from 2/16/1970 to 1/22/1973.

~ George Foreman (U.S.A.)- won the gold medal in the heavyweight division at the 1968 Olympics and held the world heavyweight title from 1/22/1973 to 10/30/1974, and again from 11/5/1994 to 11/22/1997. He is also the oldest fighter to ever win the heavyweight title.

~ Michael Spinks (U.S.A.)- won the gold medal in the middleweight division at the 1976 Olympics and held the WBA light heavyweight title from 7/18/1981 to 9/21/1985, held the WBC light heavyweight title from 3/18/1983 to 9/21/1985, held the IBF light heavyweight title from 2/25/1984 to 9/21/1985, and held the world heavyweight title from 9/21/1985 to 6/27/1988.

~ Ray Leonard (U.S.A.)- won the gold medal in the junior welterweight division at the 1976 Olympics and held the WBC welterweight title from 11/30/1979 to 6/20/1980, and again from 11/25/1980 to 2/16/1982, held the WBA welterweight title from 9/16/1981 to 2/16/1982, held the WBA junior middleweight title from 6/25/1981 to 9/16/1981, held the world middleweight title from 4/6/1987 to 11/7/1988, held the WBC super middleweight title from 11/7/1988 to 12/8/1989, and held the WBC light heavyweight title from 11/7/1988 to 6/12/1989.

~ Evander Holyfield (U.S.A.)- won a bronze medal in light heavyweight division at the 1984 Olympics and held the WBA cruiserweight title from 7/12/1986 to 7/16/1988, held the IBF cruiserweight title from 5/15/1987 to 7/16/1988, held the WBC cruiserweight title from 4/9/1988 to 7/16/1988, held the world heavyweight title from 10/25/1990 to 11/13/1992, and again from 11/6/1993 to 4/22/1994, held the WBA heavyweight title from 11/9/1996 to 11/13/1999, and again from 8/12/2000 to 3/3/2001. He is also the only fighter in history to win the heavyweight title 4 times.

~ Virgil Hill (U.S.A.)- won the silver medal in the middleweight division at the 1984 Olympics and held the WBA light heavyweight title from 9/5/1987 to 6/3/1991, and again from 9/29/1992 to 6/13/1997, held the IBF light heavyweight title from 11/23/1996 to 6/13/1997, held the WBA cruiserweight title from 12/9/2000 to 2/23/2002, and again from 1/27/2006 to 11/24/2007..

~ Pernell Whitaker (U.S.A.)- won the gold medal in the lightweight division at the 1984 Olympics and held the IBF lightweight title from 2/18/1989 to 1/18/1992, held the WBC lightweight title from 8/20/1989 to 1/18/1992, held the WBA lightweight title from 8/11/1990 to 1/18/1992, held the IBF junior welterweight title from 7/18/1992 to 12/1/1992, held the WBC welterweight title from 3/6/1993 to 4/12/1997, and held the WBA junior middleweight title from 3/4/1995 to 8/26/1995.

~ Lennox Lewis (Canada)- won the gold medal in the super heavyweight division at the 1988 Olympics and held the WBC heavyweight title from 5/8/1993 to 9/24/1994, and again from 2/7/1997 to 4/22/2001, and again from 11/17/2001 to when he retired in 2003, held the WBA heavyweight title from 11/13/1999 to 2000, and held the IBF heavyweight title from 11/13/1999 to 2002.

~ Riddick Bowe (U.S.A.)- won the silver medal in the super heavyweight division at the 1988 Olympics and held the world heavyweight title from 11/13/1992 to 11/6/1993, and held the WBO heavyweight title from 3/11/1995 to 1995.

~ Roy Jones (U.S.A.)- won the silver medal in the junior middleweight division at the 1988 Olympics and held the IBF middleweight title from 5/22/1993 to 1994, held the IBF super middleweight title from 11/18/1994 to 1996, held the WBC light heavyweight title from 8/7/1997 to 5/15/2004, held the WBA light heavyweight title from 7/18/1988 to 5/15/2004, held the IBF light heavyweight title from 6/5/1999 to 2003, and held the WBA heavyweight title from 3/1/2003 to 2003.

~ Michael Carbajal (U.S.A.)- won the silver medal in the junior flyweight division at the 1988 Olympics and held the IBF junior flyweight title from 7/29/1990 to 2/19/1994, and again from 3/16/1996 to 1/18/1997, held the WBC junior flyweight title from 3/13/1993 to 2/19/1994, held the WBO junior flyweight title from 7/15/1994 to 1994, and a