Alexander Povetkin of Russia is back on the cusp of another heavyweight world title fight after a brutal knockout of David Price on Saturday.

The WBA champion from 2011-13, Povetkin’s career stalled twice after testing positive for performance-enhancing drugs in a seven-month period in 2016.

Now, he is the mandatory challenger for the WBA belt after a fifth-round stoppage of Price with a left hook that drew gasps from the estimated crowd of 78,000 inside Cardiff’s Principality Stadium. The 38-year-old Povetkin has won eight straight fights, leaving the loss on points to Wladimir Klitschko in 2013 as his only defeat in 35 bouts.

Price was a sitting target after being hit with a right jab from Povetkin, who followed it up with a powerful left that sent the British boxer to the canvas. Price needed medical attention before getting to his feet.

Povetkin had already floored Price with a big left hook in the third round, though ended that round staggering back toward the ropes after getting hit with a left himself.

Price started his pro career with 15 straight wins but has now lost five times, four of the defeats coming against boxers who served — or would go on to serve — doping bans.

Price's close friend, former cruiserweight champion Tony Bellew, was ringside as part of the Sky Sports broadcast team. He was very upset with Price getting knocked out in that fashion.

"I'm a little bit heartbroken to be honest," Bellew said.

 "He just couldn't find the punch to get the fight over with. He hurt [Povetkin] really bad but couldn't find the punch to get the fight over with, at the start of the [next] round.

"I give him so much credit. Against all the odds, nobody gave him a chance, there were so many things that were against him. I just wish it was different. David is a brilliant fighter, a brilliant man - there is more to life than boxing."