For boxing fans who fell victim to the recent seduction of the failed negotiations for a heavyweight title unification bout this fall between Anthony Joshua and Deontay Wilder, seeing the British star face anyone else this Saturday feels like a letdown. Yet Joshua (21-0, 20 KOs), the sport's biggest star globally, will still have an interesting challenge on his hands when he enters Wembley Stadium in his native London (DAZN, 4:30 p.m. ET) to defend his IBF, WBA and WBO titles in his sixth defense since first winning the IBF crown in 2016. 

Former world title challenger and secondary WBA champion Alexander Povetkin (34-1, 24 KOs) presents a legitimate and dangerous challenge for Joshua that can't be overlooked by anyone -- especially Joshua, promoter Eddie Hearn and new streaming platform DAZN, which makes its U.S. debut -- when looking ahead to future challenges. 

Although Povetkin is 39 and needed to get up off the canvas to knock out David Price in March, the former Olympic gold medalist is as complete and experienced a fighter that is currently available to Joshua during this recent renaissance within boxing's recently dormant glamour division. 

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Povetkin, who enters on an eight-fight win streak including six by knockout, has both the power and technique thanks to his amateur pedigree to potentially become a problem for Joshua. Even more, he has the hunger as an aggressive fighter who goes for the knockout, which could make Saturday's fight a fun one considering Joshua's minor chin issues in the past. 

But the main concern when considering just how competitive Povektin has a chance to be doesn't surround his age -- heavyweights tend to mature late and stay relevant even past 40 -- or the fact that he's somewhat small at 6-foot-2 during this largely super heavyweight era which features the 6-foot-6 Joshua, the 6-foot-7 Wilder and 6-foot-9 Tyson Fury. 

The real concern with Povetkin is his history with performance-enhancing drug issues, most notably a positive test for the banned substance meldonium which cost him a shot at Wilder's WBC belt in a lucrative 2016 bout that was set for Moscow. With the relatively weak punishments he has received as a two-time offender, many openly question why Povetkin has been allowed a title shot considering his history. 

In this case, thanks to an aggressive level of testing that was made mandatory in the contract by Joshua and Hearn, the concern isn't so much that Povetkin will enter the fight dirty. The concern is whether he can still look like the same devastating fighter he has been over the past five years without the PEDs. 

The challenger Povetkin is riding an eight-fight winning streak.  Getty Images

The Joshua fight represents the biggest in Povetkin's career since he suffered his lone pro defeat in 2013 against then-unified champion Wladimir Klitschko. Although Povetkin lost every round but one on all three judges' scorecards and was knocked down four times, referee Luis Pabon did nothing to help his cause by allowing Klitschko to drape his body all over Povetkin and illegally clinch without warning or penalty. 

Although Povetkin rebounded from the loss with five straight devastating knockout wins, all against name opponents within the division, both of his next two fights following a pair of failed drug tests went the distance. 

Povetkin's name has been as troubled as it has been successful as a major player within the division dating back to his breakthrough 2011 decision win over former champion Ruslan Chagaev that saw him claim a vacant WBA regular title. 

Joshua earned the biggest victory of his own career when he got up from the deck to finish Klitschko in 2017, but the aftermath of that slugfest saw him focus much more on boxing and using his height and reach to his advantage in conservative wins over Carlos Takam and Joseph Parker. 

For Povetkin to have success, there is little question he'll need to get inside on Joshua to help overcome the 7-inch reach disadvantage he faces. But considering the hiccups Joshua has shown against punchers, there's little doubt Povetkin has the fire power and guile to fight-altering shots should he be able to do so. 

The idea of Povetkin outboxing Joshua isn't as realistic without packaging knockdowns to get there, so the Russian slugger may be better off focusing on one big punch by using his veteran tricks and roughhousing tactics to penetrate Joshua's defense and try to make it more of a fight than a technical showcase. 

While the 28-year-old Joshua enters as the rightful betting favorite, the degree to which Povetkin has been labeled by oddsmakers -- as high as +875 but some books -- seems to forget too easily Joshua's vulnerabilities. Povetkin may have age and size going against him, and he may be fresh off a comeback knockout performance in his last bout that can't be so easily forgotten. But his experience simply dwarfs that of Joshua, who is very much still a work-in-progress. 

Povetkin's 13-year pro career has featured wins over the likes of Chagaev, Takam, Chris Byrd, Hasim Rahman, Eddie Chambers and Marco Huck, so be careful not to make a mistake when handicapping his chances. Far from just another stay-busy opponent, Povetkin may find himself one punch away from turning into a very live underdog.