Former world champion Andy Ruiz Jr has vowed to carry on after losing his comeback fight to Poland’s Damian Knyba in New Jersey.

The 36-year-old heavyweight shocked the boxing world seven years ago by beating Britain’s Anthony Joshua to take his world titles.

Ruiz Jr has since been beset by injuries and was taking part in just his fourth fight since losing the rematch to Joshua in December 2019.

He looked a shadow of his former self at the Prudential Center in Newark, saved by the bell after scrambling back to his feet following a knockdown in the seventh, he eventually lost by a unanimous points decision.

Judges scored the fight 117-110, 114-113 and 114-113 in favour of the Pole, who took his record to 18 wins and one defeat, but Ruiz Jr was quick to demand a rematch.

“I don’t know, I think it was just him holding,” said Ruiz Jr, who recently signed up with British promoter Eddie Hearn.

“Every time I tried to come in, he’d hold me really tight, and I just couldn’t let my combinations go.

“He played a good game plan, but I’d love to run it back and do things a lot different.”

Joshua’s former conqueror argued that he was simply rusty after taking his first fight since drawing with American Jarrell Miller in August 2024.

“It was just a long layoff, and it was a great opponent,” he argued.

“I didn’t want to take an easy fight, so that’s why I took Damian. He’s a big guy. But we’ve got to take risks. I’ve still got it in me, man. I’ve just got to stay active and I want to fight again.”