Youth and his opponent’s right hand served DaVarryl Williamson a brutal reminder that the fight game is a perilous choice for the 40-and-over set.

Williamson, a former heavyweight contender who turns 44 next month, thought he could pursue another title bid in his main event bout against Tony Grano on Saturday night at Hard Rock Live Arena. But Grano had other ideas and ended Williamson’s title dreams with a fourth-round technical knockout before a crowd of approximately 3,000 that included former heavyweight champions Larry Holmes and Evander Holyfield.

The victory earned Grano, 31, the North American Boxing Federation title.

Grano caught Williamson with a right to the head midway through the fourth. Grano followed with solid rights to the head, and Williamson fell hard to the canvas. Referee Telis Assimenios stopped counting the knockdown, ending the bout at 2:27 of the round.

“I knew I could catch him over his left jab,” Grano said. “When the third round came around, I gathered my composure.”

After an uneventful first two rounds, Grano (20-2-1, 16 KOs) stunned Williamson (27-7) with a right to the head. Williamson immediately held onto to Grano in an attempt to avoid follow-up combinations. Grano found another opening and tagged Williamson with another right to the head.

Seemingly out on his feet, Williamson clinched again and survived the round as Grano landed another solid power punch in the closing rounds.

Earlier, Miami’s Joey Hernandez (22-1-1, 13 KOs) also scored a fourth-round TKO victory in his junior-middleweight bout against Brandon Baue (12-7).

Hernandez found his opening and dropped Baue with a right to the head. Baue beat the 10-count but Hernandez followed with a series of combinations to the head. Hernandez chased Baue to a corner and continued to land unanswered shots, forcing referee Frank Gentile to stop the fight at 1:11 of the round.

“Once I started second and third rounds, I got loose and it was time finish him,” Hernandez said.

In another bout, Hialeah resident Angelo Santana remained unbeaten with a third-round TKO win over Justin Savi.

A native of Cuba, Santana (13-0, 10 KOs) dropped Savi with a right to the head in the second round. Later in the round, Santana’s gloves appeared to have touched the canvas after Savi (26-2) caught him with a right to the head, but referee Gentile did not rule a knockdown.

Santana scored another knockdown in the fourth round but pressured Savi as soon as he reached his feet. Santana kept Savi near the ropes and connected with unanswered combinations. With Savi not mounted sufficient counter attack, Gentile stepped in between both fighters and ended the bout at 1:11 of the round.

In other bouts: junior-middleweight Omar Henry won a unanimous decision against Tyrone Selders; junior-bantamweight Thomas Snow scored a TKO over Ernest Marquez at 46 seconds of the fourth round; junior-welterweight Amir Iman scored a technical knockout over Kelvin Williams at 2:59 of the first round; heavyweight Trevor Bryant knocked out Hector Hodge at 34 seconds of the first round; junior-middleweight Esale Estimar knocked out Xavier Lugo at 2:22 of the first round.