London:Roger Federer comes face-to-face with Mario Ancic at Wimbledon again on Wednesday with the five-time champion unable to escape the memory of his 2002 defeat to the Croatian at the All England Club.
Ancic stunned Federer in the first round here six years ago in what was the world number one's last grasscourt defeat.
Federer has defeated Ancic comfortably five times since, including the 2006 quarter-finals, and has racked up 63 successive wins in total on the surface, but still it's that first meeting which still fascinates.
"It taught me not to underestimate any opponent, no matter where they're from, what technique they have, what ranking they have," said Federer of the defeat which followed his stunning 2001 tournament where he had knocked out Pete Sampras.
"I think I had a tendency, when guys maybe didn't have the proper technique or were new on tour, I would sometimes not give them the respect they deserved."
That's been a valuable life and career lesson for Federer who has since stormed to five Wimbledon titles and is braced to become the first man to win six in a row.
Ancic, a semi-finalist in 2004, has also shrugged off the significance of his 2002 heroics and has recently seen Federer in full flow from close range having lost in straight sets in the third round at the French Open.
The Croatian serve-and-vollyer missed Wimbledon in 2007 because of glandular fever and was then plagued by injury and more illness.
Ancic reached the quarter-finals for the third time with a gruelling 3-6, 4-6, 6-3, 6-4, 13-11 win over Spanish 22nd seed Fernando Verdasco.
He admits that after all his troubles, he's just happy to be back at the All England Club.
"Wimbledon means so much to me. It doesn't matter what happens at the end of the week. I really feel this is the tournament I grew up with. This is the tournament where I always felt great and always had great memories."
A lot has happened in the six years since his famous win.
Before the illness, Ancic was a top 10 player and had helped Croatia to a first Davis Cup.
But the past is past for Ancic.
"He was not Roger Federer at that time. I can sit here and tell stories about how I beat him, but actually it wasn't Roger Federer as we know him today.
"It was the last time he lost on grass and if it wasn't for that, I think people would pretty much forget about that win."