Manny Pacquiao is coming out of retirement.

The 46-year-old boxing great is scheduled to face WBC welterweight champion Mario Barrios at the MGM Grand in Las Vegas on July 19, nearly four years after his last professional fight.

"I'm back," Pacquiao posted Wednesday on social media.

Pacquiao's team announced the comeback last week, just hours after he conceded defeat in a bid for another seat in the Philippines Senate.

Pacquiao won 12 titles in a record eight weight classes from flyweight to super welterweight while becoming one of boxing's biggest draws. He will be enshrined in the International Boxing Hall of Fame on June 8.

He had announced his retirement followed a disheartening defeat to Yordenis Ugas. In what was Pacquiao's first fight in more than two years, a younger Cuban boxer beat him by unanimous decision to retain the WBA welterweight title.

Pacquiao's rags-to-riches life story and legendary career brought honour to his Southeast Asian nation, where he is known by the monikers "Pacman" and "People's Champ."

The 30-year-old Barrios, who retained the WBC welterweight belt with a draw against Abel Ramos last November, is 29-2-1 with 18 KOs.