This was one of the most hyped clashes in recent memory but it delivered – and then some.
Joshua looked like he had won it, then he looked like he had lost it, but somehow he battled back to stop Klitschko in the 11th round of a thriller in front of 90,000 fans at Wembley Stadium.
The defending IBF champion added the WBA belt to his glittering CV but this was about more than belts.
This was proving who the king of the heavyweight division is and it was the young lion that prevailed.
Not without the almightiest of scares though. Joshua floored Klitschko in the fifth and looked like he was one punch away from an early victory.
But he hit the canvas in the following round and looked out on his feet when he beat the referee’s count.
It took him two full rounds to recover before he found his rhythm again and then he ended it in the 11th.
Klitschko, who had been down twice already in the round, was being peppered with huge shots in the corner before referee David Fields called it off.
Anthony Joshua celebrates after winning an epic heavyweight title bout against Wladimir Klitschko
Joshua spoke before the fight about how he used to travel to Wembley to scour the markets for fake clothes to impress his mates.
That was before he found boxing and the riches it would bring to him.
But this was the night he was set to show he is a genuine heavyweight star.
This was the big one and, while he showed plenty of flaws, he delivered…