Two-time world champion Anthony Joshua knocked out mixed martial arts star Francis Ngannou in just the second round of their widely-hyped heavyweight clash on Saturday, with his promoter quickly declaring him the division’s “number one” fighter.

Joshua had his Cameroonian opponent on the canvas in the first round and twice more in the second in a brutal and brief exhibition of punching power.

Ngannou, 37, a former UFC heavyweight champion, was taking part in only his second professional boxing match, having lost a split decision to Tyson Fury in an October fight that saw him put the WBC champion on the canvas in the third round.

Joshua, a former unified WBO, WBA and IBF heavyweight champion, went into the fight on the back of three successive wins.