World heavyweight boxing champion Tyson Fury has criticised UFC fighter Conor McGregor for giving up too easily in his welterweight clash with Nate Diaz.

The Irishman stepped up 25lbs and was initially due to face Rafael dos Anjos, only for the Brazilian to pull out with a foot injury, resulting in Diaz taking the fight at short notice.

Diaz managed to pull off a shock result in Las Vegas, though, winning by submission in the second round on a night that also saw Holly Holm defeated in her first defence of the women's bantamweight championship.

Fury was particularly unimpressed by McGregor, though, and used his submission as grounds to claim that boxing is the "ultimate combat sport".

"Both top UFC fighters lost this weekend, Holly Holm showed more than Conor McGregor," Fury wrote on Twitter.

"The fighting pride of Ireland would not of tapped out so easy Conor McGregor I would of went sleep first. There can only be 1Tyson fury. If a man talks the bizo then go and back it up, if I say a thing I do it.

"MMA.....gets hard tap out, boxing is the Ultimate combat sport. Where 2 proper fighters stand up & fight."

Fury is expected to fight Wladimir Klitschko in a rematch of their heavyweight bout in June of this year.