Brian Viloria (left) watches as referee Zach Young gives the fallen Omar Soto the mandatory count.

MANILA — Brian Viloria, who must have discovered the fountain of youth somewhere in California, scored a sensational first-round knockout of old rival Omar Soto at the Florentine Garden in Hollywood on July 25.

Viloria, who’s turning 35 in November, floored his Mexican opponent three times right in the opening round.

The fight was stopped by referee Zach Young in the 2:02 mark.

The non-title fight scheduled for 10 rounds did not last long as Viloria stormed out of his corner and landed shots that totally stunned Soto, whom he defeated in Manila on points in 2010.

The “Hawaiian Punch” is back.

Viloria, former world light-flyweight and flyweight champion, has now won four in a row, and is surging like he’s vying for his first world title.

He took a bitter loss to Juan Francisco Estrada in Macau in 2013.

But he moved on instead of rolling over and now he’s back in the swing of things.

Viloria, who trained under Freddie Roach and Marvin Somodio and Ruben Gomez, is hoping to get another crack at the world title.

The Filipino fighter may end up fighting either Roman Gonzalez or Estrada later this year.