Romanian Simona Halep, last year's runner-up, was knocked out in the second round of the French Open 7-5, 6-1 by Croatian Mirjana Lucic-Baroni on Wednesday.
The third seed crumbled after losing the first set, managing a mere five winners in the match against the world number 70.
Halep, who usually toys with her opponents, offering a mix of pace and accuracy, was the victim this time as she never found her stride on court Suzanne Lenglen.
Lucic-Baroni, who next plays French 29th seed Alize Cornet, ended Halep's resistance with an ace.
Ivanovic survives late-night scare
Former champion Ana Ivanovic avoided a second round upset at the French Open when the Serb battled back from a set down to beat lowly-ranked Japanese player Misaki Doi on Wednesday.
The seventh seed, who beat Dinara Safina to win the title in 2008 and has returned to her best form after a slump, was outplayed initially by Doi but recovered to win 3-6, 6-3, 6-4 with the clock past 9pm local time.
She was on tenterhooks until the end though and failed to serve out the match at 5-2 in the decider, showing her frustration as she blazed a forehand wide.
Doi then held serve with a crafty drop shot but Ivanovic kept her nerve, moving 40-0 ahead on serve and sealing victory when Doi fired a backhand long.
Ivanovic will face Croatian teenager Donna Vekic in the third round.
Sharapova romps into third round
Defending champion Maria Sharapova moved easily into the third round of the French Open with a 6-3, 6-1 defeat of fellow Russian Vitalia Diatchenko on Wednesday.
The world number two, wearing a long-sleeved top despite the warm temperatures on Court Philippe Chatrier possibly due to the cold she has been suffering from, took a while to get into her stride but romped away from her 91st-ranked opponent.
Sharapova, who has won two of the last three French Opens and was beaten by Serena Williams in the 2013 final, broke serve in the first game but a double fault gifted Diatchenko a break back to 2-2.
Diatchenko then coughed up two double faults in the next game to hand the advantage back to Sharapova and another double fault brought a lukewarm first set to a conclusion.
Sharapova then powered through the second set in 35 minutes, offering up few errors.
Things will toughen up for the five-times Grand Slam champion in the next round when she faces Australia's Samantha Stosur, the runner-up in 2010 and twice a semi-finalist, who she beat in the fourth round last year.
Stosur blazes through
Former runner-up Samantha Stosur raced into the third round of the French Open with a 6-0, 6-1 victory over France's Amandine Hesse on Wednesday.
The 26th-seeded Australian, who reached the Roland Garros final in 2010 and the last four on two other occasions, had way too much power and pace for the 22-year-old wild card.
Hesse, the world number 272, was heading for a 'double bagel' at 6-0, 5-0 but a crosscourt volley saved her from utter humiliation on Court Suzanne Lenglen.
Stosur, who next faces either defending champion Maria Sharapova or her Russian compatriot Vitalia Diatchenko, wrapped up the contest in the following game with a forehand winner.