In the seventh round of Saturday night’s heavyweight title fight, one of boxing’s biggest stars fell to one knee and then staggered to the corner. Referee Michael Griffin walked over to Anthony Joshua, watched him as he made an attempt to recover and then called the fight with 1:26 remaining in the round.

With that, Andy Ruiz Jr. shocked the sport.

Ruiz’s knockout of the heavyweight champion Joshua (22-1, 21 KOs), making his U.S. debut in Madison Square Garden, was predicted by few. Ruiz (33-1, 22 KOs), a 14-1 underdog coming into the night according to the FanDuel sportsbook, scored four knockdowns of the British star, including his TKO victory in the seventh.

Joshua lost his International Boxing Federation (IBF), International Boxing Organization (IBO), World Boxing Association (WBA) and World Boxing Organization (WBO) titles with the upset.

Ruiz, a native of Southern California, is the first fighter of Mexican descent to win a heavyweight title. He was chosen as a late replacement for Jarell Miller in this fight after Miller failed a drug test.

Both fighters were knocked down in a dramatic third round, with Ruiz going first and then Joshua falling on an overhand right. Ruiz knocked the defending champ down again just before the round ended.

Ruiz knocked down Joshua again in the seventh before his fourth and final fall.