John David Newcombe was born on 23 May 1944 in Sydney. As a boy he was more interested in other sports, and he later named Ken Rosewall, Lew Hoad and Frank Sedgman as the players who inspired him. He was Australian junior champion in 1961, 1962 and 1963, and he first played a major at 15, at the 1960 Australian Championships.
His first major title came in 1965, in the Australian doubles with Tony Roche, and the pair won Wimbledon the same year. It was the start of one of the great partnerships: Newcombe won 17 major doubles titles, 12 of them with Roche, a team record that stood until the Bryan brothers passed it in 2013. In singles he won Wimbledon in 1967, losing only five games in the final against Wilhelm Bungert, and the US title the same year. He was the last amateur champion at Wimbledon and the world's top amateur that year.
He then signed with World Championship Tennis and became one of the "Handsome Eight", the tour's original professionals. He won Wimbledon again in 1970 and 1971, both times in five sets, against Ken Rosewall and Stan Smith, and added the US Open in 1973 and the Australian Open in 1973 and 1975. In 1974 he won the WCT Finals, beating a young Björn Borg, and from 3 June to 28 July he was world No. 1, the second man to top the ATP rankings.
He was a rugged serve-volleyer whose main weapons were his serve, his volley and his forehand. All his major singles titles came on grass, and the French Open was the one he never won. Counts of his major titles range from 25 to 27, depending on how his mixed doubles titles are tallied. He played on five winning Davis Cup teams, and as Australia's captain from 1994 to 2000 he led the team to victory over France in the 1999 final. He was inducted into the International Tennis Hall of Fame in 1986, together with Roche.