Roger Federer insists that Mario Ancic won't catch him out again like he did when the Croatian sent him tumbling to an embarrassing Wimbledon defeat in 2002.
The two meet in the French Open quarterfinals on Tuesday with the Swiss world number one still needled by that first round Centre Court defeat at the All England Club.
His mood wasn't helped at the time by knowing that Ancic had come through the qualifiers to deliver his stunning blow.
Four years on and Federer again finds the 22-year-old Ancic standing in his way at a Grand Slam.
"I'm not going to underestimate him like I did at Wimbledon," said Federer.
"That's not going to happen. He's a good player. He can shorten the points. He can stay at the baseline, rally, he's a tough player."
Federer, bidding to become the first man since Rod Laver in 1969 to hold all four Grand Slam titles at the same time, admits he is surprised to see Ancic thriving on the Paris clay.
The Croatian had never got beyond the third round here before this year with his natural serve-and-volley game more suited to quicker courts.
But he came into Roland Garros having reached the semi-finals at the Hamburg Masters and the last eight in Rome as well as helping Croatia to the World Team Cup in Dusseldorf.
{{/usCountry}}But he came into Roland Garros having reached the semi-finals at the Hamburg Masters and the last eight in Rome as well as helping Croatia to the World Team Cup in Dusseldorf.
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