Oeiras hosts the Portugal Open from April 26th to May 04th. This tournament began as an ATP event in 1990, and became a combined men's and women's tournament in 1998 – making it one of the only four
European spring clay court stops (as Roland Garros, Rome, Madrid) to feature both tours playing side-by-side. Four former World No. 1 players have won the Portugal Open: Thomas Muster, Carlos Moya, Juan Carlos Ferrero and Roger Federer.
The Organization of the Portugal Open already confirmed the presence of the Swiss Stanislas Wawrinka and the Portuguese João Sousa, in this year’s event. The Swiss is the current holder of the title and the Portuguese has made history by reaching the 42nd place of the world ranking, the best achieved by a Portuguese tennis player.
For the 25th edition of the major tennis tournament in Portugal, Stanislas Wawrinka will try to defend the title won in 2013. This tournament also features names like the Canadian Milos Raonic, number 12 in the world, the Frenchman Benoit Paire, number 31, and Spaniard Pablo Andajar, number 35.
The Portugal Open also features a strong female batch, with the presence of three Grand Slam tournaments champions: Samantha Stosur (number 20), Svetlana Kuznetsova (number 30) and Francesca Schiavone (number 46). The list is also headed by, the Italian Roberta Vinci and the current champion Anastasia Pavlyuchenkova.
Source - http://en.portugalopen.pt/