Former tennis player Kosei Kamo, one of only two Japanese men who have won a title at a Grand Slam tournament after World War II, has died of a heart attack, the Japan Tennis Association said Thursday. He was 84.

Kamo, who teamed up with Atsushi Miyagi to capture the 1955 U.S. Open men's doubles crown, passed away on Jan. 6, the association said.

The Tokyo native, who served as an adviser to the association, teamed up with Miyagi at the 1955 Davis Cup to defeat the Philippines and give Japan its first-ever victory in the eastern zone final.

The duo went on to win the U.S. Open doubles tournament, which at the time was held separately from the singles competition, becoming the first Japanese men to claim a major title since Tatsuyoshi Miki won the mixed doubles with Britain's Dorothy Round at Wimbledon in 1934.