Zhang Zhilei (left) and Deontay Wilder pose during a news conference in London on Monday. Wilder has hinted his fight against Zhang, on the undercard of Dmitry Bivol and Artur Beterbiev’s undisputed light heavyweight world title fight in Saudi Arabia on June 1, could be his last. ACTION IMAGES VIA REUTERS

Not a former champ in the opposite corner, nor a recent defeat — and definitely not his age — can deter China's heavyweight boxer Zhang Zhilei from punching his way back into title contention once more.

Despite suffering a tough loss by majority decision to Joseph Parker last month, Zhang, aka the "Big Bang", has vowed to fight back to winning ways on June 1, when he is matched up against former WBC heavyweight titleholder Deontay Wilder of the United States on the undercard of the light heavyweight title bout between Dmitry Bivol and Artur Beterbiev in Saudi Arabia.

Zhang, who could've secured himself a title shot with a win over Parker on March 8, refused to let the setback derail his world championship ambitions, as he vows to blow up the "Bronze Bomber" — as Wilder is known in the ring — and use the fight as a stepping stone in his bid to challenge for a world title in pro boxing's top division, currently ruled by Britain's Tyson Fury (WBC) and Ukraine's Oleksandr Usyk (WBO, WBA and IBF).

The bout was confirmed at a news conference in London on Monday, as part of the blockbuster "Matchroom vs Queensberry" five-on-five event, a mouthwatering five-bout series between two famous British promotions as a buildup to the unification clash between Russia's Beterbiev, the WBO, WBC and IBF champion at 175 pounds (79 kg), and his fellow WBA champion, Bivol, in the Saudi capital, Riyadh.

A bout against Wilder, who was considered the division's heaviest puncher in his prime, is expected to serve up a quality test for Zhang's credentials as a future belt contender, with the 40-year-old Chinese southpaw hailing his 38-year-old American foe as a dangerous test.

"Wilder is a heavy gunner with a lot of power. I have to be very careful with him," Zhang said during the news conference.

"I am a skillful and powerful puncher as well. When the opportunity presents itself, I will not hold back."

After building his name in the amateur ring and winning an Olympic silver medal (+91kg) at his home Games in 2008, in 2014, Zhang decided to take his talent to the pro ranks, and has since progressed into a rare heavyweight boxing success from Asia, underlined by two straight stoppage wins over Britain's former world champ Joe Joyce last year.

As the oldest among the world's top heavyweights, Zhang's conditioning issue over a full 12-round battle has been questioned, by fans and pundits alike, since he was outboxed by Parker last month. Also taking place in Riyadh, Zhang landed very few significant punches on Parker, other than two knockdowns in the third and eighth rounds, all while getting worn out by the New Zealander's mobility and quick one-twos.

Zhang's conservative attack, especially in the last two rounds, when he still had a legitimate chance to at least push for a draw to keep his WBO interim belt, had even prompted some fans to speculate that he'd intentionally lost the bout to trigger a rematch clause on his contract with Parker's team.

The native of Central China's Henan province, however, hit back against doubts about his integrity and fitness on social media.

"Such comments are insulting to myself and the sport of boxing," he told sina.com in a recent interview. "As a pro, we need to keep winning to earn more money (appearance fees), and a loss results in a huge drop in market value. It just doesn't make any sense to earn more money as a loser (from a rematch)."

"My loss to Parker was down to my carelessness and tactics that were not appropriate," Zhang said in a CGTN interview aired on Tuesday.

"As for my advantages facing Wilder, I am a southpaw, Wilder has fought very few lefties before. I am confident of ending the bout in the early rounds," said Zhang, who keeps a career record of 26-2-1 with 21 KOs.

Wilder, who has knocked out 42 opponents in his 43 career wins, said he sees the fight as a career flourish.

"I'm holding it as my last dance, my last chance," said Wilder, who wrested the WBC title from Luis Ortiz via KO in November 2019, but lost it to Fury in his first defense three months later.

"I respect Zhang, he's a good fighter. But it's my time, I've been through a lot. I had to regroup and get myself together. I'm just ready to do what I'm known to do, be the Wilder I am," he said at the news conference.

"I am not playing around this time. I have nothing to lose, but plenty to gain. I can feel the sensation and desire in my heart again — and that hunger. The beast is coming back."

Zhang's promoter, Frank Warren with Queensberry, said the bout has something special in store and that fans won't be disappointed.

"This is something that people will talk about in the years to come," said the Hall of Fame promoter. "Both fighters' careers are on the line. There is so much at stake. This fight's winner is going to be back at the top table. That's how competitive this fight is going to be."