He won his first top-level singles title in 1986 at Buenos Aires. In 1988, he captured both the singles and doubles titles at São Paulo. In March he upset world # 2 Mats Wilander, 6–0, 7–5, in Orlando, Florida. In March 1989 Berger upset world # 3 Boris Becker, 6–1, 6–1, in Indian Wells. In May he upset world # 3 Mats Wilander, 6–3, 6–4, in Rome. In August Berger beat world # 3 Stefan Edberg, 6–4, 6–2, at Indianapolis.
