Pre-tournament favourites Jelena Jankovic and Elena Dementieva suffered shock defeats in the second round of the WTA event in Indian Wells on Saturday.
Second seed Jankovic was upended 6-4, 6-4 by Anastasia Pavlyuchenkova of Russia while third seed Dementieva was beaten 7-6, 2-6, 6-1 by Czech Petra Cetkovska.
Serbian Jankovic was well below her best against world number 42 Pavlyuchenkova and admitted she was totally out of sorts.
"I'm struggling in this moment to find my game overall and find the confidence on the court," Jankovic said.
"Obviously she was the better player. But I'm not at my level. That's the case. I'm trying to find that game and trying to come back into form, but I'm struggling at the moment.
"I wish I had a magic stick and could just fix my game and just start playing awesome tennis again. I would like it to be that way, but sometimes it's not."
Russian Dementieva hit a total of 14 double faults, eight in the first set, as she suffered her earliest defeat in the Indian Wells tournament since 2003.
Dementieva, who began the year with back-to-back titles in Auckland and Sydney and then reached the semi-finals at the Australian Open, blamed her hectic schedule so far in 2009 for her lacklustre effort.
"I just think my mind wasn't there," she said. "I was not really excited about playing this match and I just didn't play at all.
"I think I should not have come here because I did not have enough time to recover after playing so many matches at the beginning of the year. I needed a much longer break to get ready to play at my best."
World number 71 Cetkovska, in her first Indian Wells appearance, snatched the first set 7-2 on a tiebreak. Dementieva levelled in the second set before falling apart in the third.
The 24-year-old Cetkovska said the victory was the best of her career.
"Every single opportunity I had, even if I could make a mistake, I tried to be aggressive," she said. "That was what I had in my head all the time."
Fifth seed Ana Ivanovic advanced to the next round but was made to fight hard for a 6-4, 6-3 victory over Belarussian Anastasia Yakimova.
"It was just a case of committing and going for some shots that I would maybe do in practice," Ivanovic said.
"Just trying to get some confidence and also experimenting a little bit with my game, because I haven't played many competitive matches."
Seventh seed Agnieszka Radwanska of Poland had to come from behind to beat Australian Sam Stosur 3-6, 6-3, 7-5.