American wildcard Vania King came from a set down to beat Anne Kremer of Luxembourg in the Pacific Life Open first round on Thursday.
The 19-year-old, who clinched her first WTA title at the 2006 Bangkok Open in her rookie season, sealed a 4-6, 6-3, 6-4 victory after a two-and-a-half-hour battle.
Seeded players received a first round bye in the tournament at the Indian Wells Tennis Garden.
"I started off really nervous and she played better and better in the first set," King told reporters after winning her second Tour match out of six this year.
"At the end of the first set, I changed my strategy and that worked out well. I was really happy to come out with the win after just fighting."
King, who next meets 31st seed Tathiana Garbin of Italy in the second round, was sidelined for three weeks last month with a viral illness.
"My body isn't 100 percent but I've been trying the best I can," the Californian said. "I think I'm ready. Every day I've been playing better and better. I'm just happy to be out here."
In other women's matches on Thursday, Germany's Angelique Kerber swept past Russian Ekaterina Bychkova 6-1 6-2 and Romania's Ioana Raluca Olaru beat Yuan Meng of China 6-4 6-4.
The top women's players enter the fray on Friday when Australian Open champion and fifth seed Maria Sharapova takes on French qualifier Stephanie Cohen-Aloro and second-seededSvetlana Kuznetsova faces fellow Russian Ekaterina Makarova.
In the men's event, Swede Robin Soederling crushed Frenchman Sebastien Grosjean 6-3, 6-3 in a first-round match on Thursday and Jonas Bjorkman, also of Sweden, edged past Italian Filippo Volandri 6-3, 7-6.
World number one and top seed Roger Federer, who was upset 6-3, 4-6, 6-0 in the second round last year by Argentina's Guillermo Canas, plays his first match on Saturday against Spaniard Guillermo Garcia-Lopezor Argentina's Sergio Roitman.
Spaniard Rafael Nadal, who won the 2007 title with a 6-2, 7-5victory over Serb Novak Djokovic, has been seeded second with Djokovic third and Russian Nikolay Davydenko fourth in the opening Masters Series event of the season.