Jarrell Miller was running out of time and chances to climb back into the picture of the top contenders in the heavyweight division, but he made the most of Saturday’s headline matchup with a 12-round unanimous decision over Lenier Pero at the Fontainebleau Las Vegas.

The scores were 117-111, 117-111 and 115-113, all for Miller.

The mauling bout saw Miller take over in the second half. The fighters pawed at one another in close quarters for most of a muted heavyweight fight.

Pero, a southpaw from Cuba who entered the fight ranked No. 2 in the division by the WBA, was intent on cementing his status. He was highly effective in the first three rounds, but he soon began to fade.

Miller, a 37-year-old from Brooklyn, New York, is a relentless pressure fighter who began to systematically wear down Pero over the course of the early rounds. In a methodical fight of attrition, Miller – who outweighed Pero by more than 50lbs but still came in 12lbs lighter than his previous bout – showed a strong motor.

Miller’s high volume of punches thrown dwarfed Pero's output, and whenever Pero seemed to have success, Miller would throw an onslaught that would override it. He picked up his pace in the second half of the fight to wear down Pero in a fight that won’t win a lot of style points but that put Miller – ranked only by the WBA, at No. 9 – back into the mix for some of the biggest fights at heavyweight.

With the win, Miller, 28-1-2 (22 KOs), became the WBA heavyweight mandatory.

Pero, meanwhile, absorbed the first loss of his professional career, slipping to 13-1 (8 KOs).

Lucas Ketelle is the author of “Inside the Ropes of Boxing,” a guide for young fighters, a writer for BoxingScene and a member of the Boxing Writers Association of America. Find him on X at @BigDogLukie.