When Anthony Joshua and Wladimir Klitschko face off in front of a record-breaking 90,000 fans at Wembley Saturday night, there will be a difference of 50 fights and 314 rounds between them.

Now 41, with many claiming his best years are behind him, Klitschko has a wealth of experience on his side to combat Joshua’s young legs and explosive power.

Ukrainian Klitschko has, at one time or another throughout a glittering 21 year career, held the WBA, IBF, WBO and IBO heavyweight titles.

Up until his shock defeat to Tyson Fury 18 months ago, the Ukrainian was undefeated for over a decade — a run dubbed the “Klitschko era” due to his and older brother Vitali’s dominance of the heavyweight division.

The 27-year-old Joshua, on the other hand, has not only endured just a quarter of the professional fights Klitschko has, he’s barely even had to absorb a punch.

Dillian Whyte’s powerful left hook, which made Joshua’s legs wobble all over the ring during their British heavyweight title bout in 2015, is the only real test of his otherwise untried chin.

The age gap between the fighters is such that Klitschko has been boxing for the same amount of time Joshua has been alive.

The 27-year-old Briton goes into the fight defending his IBF title, while also trying to win the WBA and IBO titles vacated by Fury after he tested positive for cocaine.

“I don’t hate Klitschko, I don’t dislike him, but I want to beat him,” Joshua told hoards of adoring fans after tipping the scales at 250.1 lbs at Friday’s weigh in.

It’s the heaviest Joshua has been during his short but, so far, straightforward career.