New Delhi:Maria Emilia Salerni of Argentina upset top-seeded Sania Mirza 6-2, 7-5 on Tuesday to reach the second round of the Grand Prix SAR Princess Lalla Meryem in Morocco.
Sania is currently ranked 51st in the WTA rankings, while Salerni is ranked 213th in the world.
The Morocco Open claycourt tournament is a tier-IV event, and is seen as a tune-up event for the French Open. Sania had earlier advanced to the second Round of the doubles event alongside American Vania King.
Sania made history by becoming the first Indian ever to be seeded first at a WTA Tour event, being given the top billing in both the singles and doubles competitions.
In other matches, fifth-seeded Jill Craybas of the United States beat Yulia Beygelzimer of Ukraine 6-4, 6-1, and Milagros Sequera of Venezuela also advanced when No 3 Virgine Razzano of France retired due to a left thigh injury, having lost the first set 3-6 but winning the second 7-6 (7).
Julie Ditty beat fourth-seeded Anastasia Rodionova 7-5, 7-5, but No 7 Camille Pin and No 8 Anne Kremer both advanced.
Pin beat Stephanie Dubois 6-1, 6-4, and Kremer downed Fatima Zahrae El Allami of Morocco 6-0, 6-2.
Also, Aleksandra Wozniak, Caroline Wozniacki, Neha Uberoi, Timea Bacsinszky, Sandra Kloesel and Youlia Fedossova won their first-round matches.
Wozniak beat Laura Pous Tio of Spain 6-4, 6-1; Wozniacki downed Ahsha Rolle of the United States 6-3, 6-4; and Uberoi topped Sorana Cirstea of Romania 6-2, 6-3.
Bacsinszky beat Olga Savchuk of Ukraine 6-0, 6-3; Kloesel defeated Nadia Lalami of Morocco 6-0, 6-3; and Fedossova knocked out Alina Jidkova of Russia 6-3, 5-7, 6-3.
Romania's Ioana Raluca Olaru progressed after beating Alla Kudryavtseva of Russia 7-5, 6-4. (With AP inputs)