David Nalbandian and James Blake were both high-profile casualties in the second round of the French Open on Thursday.
Nalbandian, the sixth seed, managed to throw away a two-set lead to lose to French wild-card Jeremy Chardy, the world number 145.
The Argentine surrendered 3-6 4-6 6-2 6-1 6-2 and appeared to be moving uneasily in the latter stages of a match that lasted over three hours.
He led 2-0 in the deciding set before Chardy - cheered on by a raucous crowd on Court Two - produced a string of dashing winners to reel off six games in a row and secure victory.
Blake, the seventh seed, fared even worse, going down in four sets against Ernests Gulbis.
The Latvian teenager triumphed 7-6 3-6 7-5 6-3 to earn his first success over top-10 opposition this season.
Blake was one of five American men to reach the second round in Paris and had been hoping to join compatriot Wayne Odesnik in the last 32.
But world number 80 Gulbis had other ideas and produced fine display, particularly in the final two sets, both of which he dominated.
The result was sealed in two hours and 36 minutes with a down-the-line backhand winner and earns the 19-year-old a third-round appointment with either Nicolas Lapentti of Ecuador or American Bobby Reynolds.
Fourth seed Nikolay Davydenko had no such problems, easing his way to a 7-6 6-2 6-2 win over fellow Russian Marat Safin.
There was an anxious moment for Davydenko, who saved three set points serving at 4-5 in the opening set.
But the two-time semi-finalist at Roland Garros recovered to force a tie-break, which he took 7-4.
And that provided the platform for Davydenko to dominate the remainder of the match, which lasted two hours and 16 hours, and book a third-round date with Croatian 28th seed Ivan Ljubicic.

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