Anthony Joshua defends his IBF, WBA, and WBO heavyweight titles tonight against Alexander Povetkin in the knowledge that he may just end another career.

The 28-year-old fights at Wembley Stadium for the first time since his 11th-round stoppage of Wladimir Klitschko led to a fine and respected champion’s retirement while establishing him among the world’s leading fighters today.

If with Joshua’s past two fights there was a frustration that he did not defeat Carlos Takam and Joseph Parker as convincingly as he would have hoped, there is also the reality that, similarly to Klitschko, they are yet to recover from those defeats.

Takam had been the favourite against Dereck Chisora in July but lost via a shock stoppage that suggested the punishment he absorbed from Joshua had ensured his decline, and on that same evening Parker unexpectedly lost to Dillian Whyte, ending his options at world level.

Russia’s 39-year-old Povetkin, whose reputation will never fully recover from the damage caused by two failed drug tests, secured Saturday’s fight by becoming Joshua’s mandatory challenger five years after last fighting for a world title, and is unlikely to do so again if he suffers his second defeat.

By fighting Joshua, Povetkin is ultimately risking never fighting again, and asked about his streak of damaging careers, Joshua said: “It does happen, it’s a tough game. It’s not only the training camps, it’s the actual fighting; 10, 11 rounds of punishment.

“It does take a lot out of (opponents). Obviously I’ve not been out there knocking people out (in the early rounds) like I used to, but it’s different, top-tier fighters at the top end. I’m fighting the best of the best and it’s tougher, but ultimately they’re getting someone just as tough and it does take a lot out of them.

“It does take something out of (even) these tough guys.”

Povetkin’s defeat by Klitschko came on the same night Joshua made his professional debut by stopping the little-known Emanuele Leo at the 02 Arena, when even for all of the excitement surrounding Joshua, it was Klitschko-Povetkin that demanded the greatest attention.

The then-raw professional was monitoring Klitschko’s career, and discussing the way he and Povetkin have since been brought together, he said: “It’s crazy. But you’ve got to give him respect because he’s been on top of his game since that time; what he’s done to stay there, and he’s here now, having been through a lot of issues, trials and tribulations.

“He’s stayed relevant, so it shows he’s mentally tough. He’s been around; he’s stayed strong, (and) he’s definitely learned a lot since.”

At yesterday’s weigh-in the champion hit the scales at 17st 8lbs 5oz, providing further confirmation of the physical advantages he holds over the significantly smaller, 15st 12lbs Povetkin, but the Russian said: “I’m paying a lot of attention to tactics in this fight as that’s going to be very important. Counter-attacks and my own attacks are so important.

“This fight is all about experience. I am aware that ‘AJ’ is world champion, but I’ve been in massive events before, so this is not new to me.”