Saul 'Canelo' Alvarez produced a devastating uppercut to leave a distraught Billy Joe Saunders unable to rise from his stool after eight rounds of their world title unification bout.

Just as Saunders looked to be gaining a footing, the Mexican found a shot which caused an instant swelling over the British fighter's right eye.

Saunders' trainer called the bout off, with his fighter unable to see.

"I think I broke his cheek," said Alvarez. "The truth is I knew it."

Alvarez, 30, added: "I guessed in the corner and told my trainer Eddie Reynoso 'I broke his cheek'."

Within seconds of landing the pin-point blow - made more forceful by the fact Saunders was crouching into the shot - Alvarez raised his hands in front of his rival, ruthlessly letting the 73,126 in attendance know that he had broken the resistance of a man now at his mercy.

Saunders, 31, was taken to hospital with a suspected broken eye socket, an injury which has proven difficult to overcome for the likes of British fighter Kell Brook in recent years.

As an emotional Alvarez was left in the ring thanking what was a record indoor crowd for a boxing event in the US, footage on the big screen inside Arlington's AT&T Stadium showed a heartbroken Saunders visibly in pain on his walk back to his changing room.