Guillermo Vilas was born in 1952 in Mar del Plata, Argentina, where he grew up. Few players have been embraced so warmly beyond their own country as the "Young Bull of the Pampas". He first drew attention at the 1973 French Open, where he beat the defending champion Andrés Gimeno, and in 1974 he won the season-ending Masters on the grass of Kooyong in Melbourne.
His 1977 was one of the great seasons in the game's history. He won 17 of the 33 tournaments he entered, matching Rod Laver's record, with 145 wins against 14 losses, and he put together a winning streak of 46 matches, an Open Era record. Among those titles were the French Open and the US Open. The streak ended when he quit a match in disgust at his opponent's racquet, a type that was banned shortly afterwards. He finished the year ranked No. 2.
He was a player built for clay, and grass seemed foreign to him, yet his record at the Australian Open was excellent: he won it in 1978 and 1979 and was the runner-up in 1977. At Roland Garros he reached four finals; apart from his 1977 title he could not get past the Swedes, losing to Björn Borg in 1975 and 1978 and to a 17-year-old Mats Wilander in 1982, his last major final.
He finished his career with four major singles titles and 62 singles titles, the same number as Borg, which placed him fifth among the all-time winners at the time.