As a junior, González won the US Open boys' doubles (with compatriot Nicolás Massú) in 1997, and the French Open singles (defeating a young Juan Carlos Ferrero in the final) and doubles (with Venezuelan José de Armas) in 1998. That year, at 17, he made his Davis Cup debut in Chile's tie against Argentina, losing in four sets to Franco Squillari. He won his first Davis Cup tie in a doubles rubber partnering Massú. González reached as high as No. 4 in the world in singles and No. 2 in doubles.