The Estoril Open 1990 took place from April 2nd to 8th, 1990 and was the first edition of the tennis clay court tournament in Oeiras, Portugal . The tournament was part of the World Series and was part of the ATP Tour . The tournament was held in men's singles and men's doubles. 32 players competed in singles and 16 pairs of players in doubles.
At the first Estoril Open , eight players were seeded, of which only four made it past the first round. No. 1 seeded US American Jay Berger failed in the quarterfinals. The finals were played by the Spaniard Emilio Sánchez , who was seeded number 3, and the unseeded Argentine Franco Davín . Sánchez was able to prevail in two sets with 6: 3 and 6: 1.
There were four pairings in doubles. The doubles for the Spaniards Emilio Sánchez and Sergio Casal were seeded at No. 1 and played the final against the unseeded Italians Omar Camporese and Paolo Canè . Sánchez and Casal prevailed in three sets with 7: 5, 4: 6 and 7: 5. For Emilio Sánchez it was the second title in the tournament after winning the individual competition.