Anthony Joshua has exacted revenge on Ruiz Jr six months after losing his belts in one of the biggest upsets in boxing history.
Their clash came six months after Ruiz pulled off one of the biggest shocks in the sporting history.
However, Joshua gave him little chance to upset him again, forcing Ruiz to hit the canvas in the third round.
Although Ruiz showed incredible powers of recovery, he tried to drop Joshua twice before the bell rang for the end of the session.
In the first round, Ruiz took the centre of the ring, backing Joshua up but without landing anything and was then cut by a big right hand at the end of the session.
Joshua opened the cut in the opening minute of the second round and boxed well but the challenger was also cut around his eye after a clash of heads.
Ruiz began to inch forward in the fourth round and get inside Joshua’s guard and managed to land a right towards the end of the session.
Joshua responded well in the next stanza however, landing a backhand of his own as he established a lead on the scorecards.
And after Ruiz landed a left hook in the sixth, Joshua dominated the rest of the round.
The rivals briefly went toe-to-toe in the seventh round with Joshua landing the better shots.
Ruiz landed several right hands in the eighth as the challenger began to tire.
But the champion could not get close enough in the next session as Joshua held firm with his jab.
The Mexican-American’s reign as champion was slipping away and he could do little about it.
And eventually, it was up to the judges to seal his fate.