Anthony Joshua has become the unified heavyweight champion of the world by adding the WBA belt to his IBF title with an 11th-round stoppage of Wladimir Klitschko at Wembley Stadium.

The 27-year-old Briton was knocked down in the sixth round of an exhilarating fight but showed determination to bounce back and twice had Klitschko on the canvas in the penultimate round before the referee stepped in.

After a fairly even start, Klitschko upped the ante at the start of the fourth, connecting with a two-fisted attack early on, and although Joshua steadied himself, he ended up being outboxed for the first time in the bout.

Round five saw Joshua put Klitschko down on his knees with a strong left hand, but the Ukrainian veteran responded with a number of uppercuts which left his English opponent on the ropes.

The home fans then feared the worst in the sixth when Joshua was hit with an enormous right which had him down on the canvas, but he managed to survive until the end of the round.

Klitschko was unable to finish off his opponent in the seventh, which turned out to be more sedate than the previous two, and by the eighth, Joshua appeared to have recovered.

Both fighters continued to give their all until the 11th round saw Klitschko sent down with a brutal uppercut followed by an attack which left him on the canvas for the second time in the fight.

Even though the challenger stood, he was dropped by a left hook again moments later, and then stood again, only for referee David Fields to stop the fight with Klitschko pinned against the ropes and offering little response to Joshua's ambush.