In Japan, people expected him to rap because of his race, he said, so during a tough financial period, he obliged. He married a Japanese pop singer, and they now live in Harlem.

In China, if he was short of cash between tournaments, he would visit a gym, where locals would invariably direct him to the basketball courts. He’d ask to play Ping-Pong and would allow himself a loss. Then he’d put some money on the table and request someone better. He’d lose again. Then he would demand an even better player, double or nothing. That time, he’d win.

“It was my China hustle,” Green said.

Back in New York, table tennis was becoming a thing, something that hipsters had decided to reclaim from suburban basements and dank rec centers. A pair of filmmakers threw what they called “naked” Ping-Pong parties. There was no nudity involved, but the name was a lure.

Among the star attractions was Green, who played exhibition matches with Kazuyuki Yokoyama, a Japan-born former software executive who likes to play in sequined boxers and the occasional feather boa.

Soon, the crowds overflowed from the film producers’ Tribeca loft. In 2009, Spin, a Ping-Pong social club with mood lighting and a lounge vibe, was born. There are now eight outlets in North America.

“It’s kind of a dorky sport,” said Franck Raharinosy, one of Spin’s co-founders, whose parents are from Madagascar and France. “Wally, from the moment you saw him, he was different. He was cool.”

Susan Sarandon, the actor, joined the New York table tennis community. She, too, added glamour. At the Shanghai International Film Festival in 2011, she brought along Green for a stroll down the red carpet.