As an amateur, Palomino won the 1972 National AAU Light Welterweight Champion at 137 lb., defeating eventual Olympic gold medalist Ray Seales.

[7] He was discharged from the Army later that year and enrolled at Orange Coast College and later Long Beach State, where he obtained a degree.

He and Zovek Baraja had two bouts that year, the first one resulting in a ten-round draw and the second one being a nine-round knockout win for Palomino.

Palomino became a world champion on the night of June 22 of that year at Wembley Arena, after Stracey eventually succumbed to a blistering body attack and was put on the canvas twice from left hooks to the liver.

[12] He waited six months for his next fight, against another very popular boxer of Mexican background: cross-town rival Armando Muñíz.

[18] His championship run ended in 1979, when he traveled to Puerto Rico, where he was defeated on January 13 by hometown boxer Wilfred Benítez via a controversial fifteen-round split decision.

Referee Zach Clayton scored the fight 145–142 in Palomino's favor, but judges Jay Edson and Harry Gibbs disagreed.

In 1980, Miller Lite beer signed Palomino as a spokesman as part of a television commercial campaign that also included Walt Frazier and other noted athletes.

[23] He participated in a number of movies, such as Fists of Steel,[24] and television series, before deciding to launch a boxing comeback at the age of 48, in 1997.

[27] On March 14, 1980, his younger brother, Paul Palomino – a member of the U.S. boxing team en route to Poland for a competition – was killed in the crash of LOT Polish Airlines Flight 007.