Young heavyweights put on a show in Ontario

What Ontario fans missed in losing a bout between two veteran Southland welterweights Sunday was eased by the promising showings of two heavyweights.

England’s Joe Joyce and Nigeria’s Efe Ajagba — both 2016 Olympians — revealed the attributes that make them favorites of veteran promoter Richard Schaefer in his rebuilding stable.

Joyce (6-0, six knockouts) showed the offensive-minded lessons he’s gained under trainer Abel Sanchez in Big Bear by cutting off the ring, pounding the body and unleashing heavy hands en route to a fifth-round knockout of Eastern European Iago Kiladze (26-4) in a Premier Boxing Champions event at Citizens Business Bank Arena.

Joyce, 33, knocked down Kiladze three times in the bout, starting with a body shot and right to the head in the second, a body barrage in the third and a left hook in the fifth.

“I’m all action, heavy punches and explosive,” Joyce said after his U.S. pro debut. “Abel has given me great pointers and tactics and the work up there is intense. … I’ll be back training there, hopefully for the [Dec. 1 Deontay] Wilder-[Tyson] Fury undercard.”

The last time Ajagba entered the ring, he was stunned to watch his planned opponent, Curtis Harper, leave the ring right after the first bell rang.

On Sunday, Ajagba (7-0, six KOs) battered previously unbeaten foe Nick Jones with hard rights, and as the fighters moved to a neutral corner, Ajagba belted Jones with another power punch to the head. Jones crumbled to the canvas, and the fight was waved off 2 minutes, 25 seconds into the first round.

“Now we know why my last opponent walked out of the ring,” Ajagba said. “He was afraid that was going to happen to him.

“I watched tape of Jones and knew he was slow. I was ready to attack the minute I got into the ring. I want anyone that my management will put in front of me. I can’t wait to get back in the ring.”

Sunday’s originally scheduled main event between Victor Ortiz and John Molina Jr. was scrapped last week when former welterweight champion Ortiz was arrested and charged with three sexual assault felonies in Ventura County.

Former 140-pound title challenger Molina said he has interest in a bout with former 140-pound champion Brandon Rios of Oxnard by the end of the year.

“I get” why the Ortiz fight was scrapped, “especially in the day and age we live in. It’s an unfortunate situation with an accusation from an [alleged] victim and it needs to be handled to where it doesn’t look like PBC is supporting an alleged rapist,” Molina said.

In the elevated main event, Texas super-bantamweight Brandon Figueroa (17-0, 12 KOs) closed an action bout against former featherweight title challenger Oscar Escandon with a destructive right uppercut that knocked out Escandon 1:42 into the 10th and final round.

In other action, Santa Maria bantamweight Jose Balderas (5-0) said he “got the rounds I needed” by winning a four-round unanimous decision over Mexico’s Ivan Martino, and middleweight Joey Spencer (5-0) of Union City knocked out Cory Macon in the first round.

lance.pugmire@latimes.com

Twitter: @latimespugmire