After the defeat to Gomez, Hernandez won four bouts in a row, including a win over future title challenger Cleo Garcia of Nicaragua. This allowed him to challenge the WBC world champion, Mexican Carlos Zarate. Zarate was another heavy puncher who came into the championship fight, held at the Roberto Clemente Coliseum in San Juan on April 22, 1978, with a record of 49 wins and no losses, with 48 of those wins by knockout. The bout's referee was Richard Steele. Hernandez gave the champion a serious test, lasting until round 13 when he lost by technical knockout. Hernandez rebounded by outpointing future world title challenger Enrique Sanchez over ten rounds in Sanchez's home country, the Dominican Republic, but he followed that by losing by six round disqualification to Jose Jimenez, also at the Dominican Republic. He then fought Edwin Rivera (not to be confused with Edwin Luis Rivera. another local featherweight prospect of the time) for the vacant Puerto Rican bantamweight title on September 9, 1979, winning the title by a sixth-round knockout. This was, however, considered a mismatch by island boxing experts since Rivera was only 1-0 coming into that fight, compared to Hernandez's record of 29 wins, 6 losses and 1 draw (Rivera eventually retired with a record of 2 wins, 2 defeats and 1 draw). On March 29, 1980, Hernandez challenged the future world Bantamweight champion Jeff Chandler for Chandler's NABF and USBA bantamweight titles at Resorts International hotel in Atlantic City, New Jersey Despite going the distance with Chandler, Hernandez lost a 12-round points decision in his last fight of major significance. He then went to South Africa to fight Bashew Sibaca at East London, Eastern Cape, but he would lose that bout by ten-round decision, before returning to the Dominican Republic to fight Sanchez in a rematch, this time being knocked out in three rounds. Hernandez kept fighting, having bouts in Yauco, Puerto Rico and in Phoenix and Tucson, Arizona, Miami, Florida, Reno, Nevada, and Sacramento, California, where he suffered a first-round knockout at the hands of Henry Rodriguez, on December 18, 1985, after which he retired. He never again sought to fight on as a professional boxer, being able to stay in retirement. Three of Hernandez's conquerors, Chandler, Gomez and Zarate, are members of the International Boxing Hall of Fame. Apart from those three world champions, Hernandez also faced 5 other boxers who participated in world title fights, these being Illueca, Garcia, Sanchez, Sibaca and Fred Jackson.