THERE IS a diamond still nestled in the middle of the men's draw. His name is Marat Safin and no one has spoken too much about him yet because they are afraid if they blink he's gone. But Safin, if he can get past Spain's Feliciano Lopez in their quarter-final today, is a player who on a given day could beat Roger Federer, the man he is scheduled to meet if both reach the semi-finals.

Safin is the maverick in the pack, the self-destructive genius with the talent to turn the screw on the world number one. He has always been a dangerous player but this year came in from a slow, long slide down the rankings and slipped into the tournament undetected by radar. Four unseeded players have made it into the last eight. Nobody would have guessed the Russian would be one of them.

But as the draw clears and horizons become visible, Safin sits in the top half with just the 31st seed, Lopez, to shift for a place in the semi-final. That he beat Stanislas Wawrinka, the 13th seed, in the last round is inconsequential in terms of what shape he will be in for Lopez, except that it indicates Safin is playing at a much higher level than his ranking of 75.

It is only his second time in the quarter-finals; he reached this stage in 2001 before losing to the eventual champion Goran Ivanisevic. He has not been to a Grand Slam quarter-final since the 2005 Australian Open, when he went on to win his second Grand Slam title over four years after his first, at the US Open in 2000.

Lopez, who has beaten Safin four times in their last five meetings, is at this stage for the fourth time. In 2005 he had a smooth run against three players ranked outside the top 100 before losing to Lleyton Hewitt in the quarter-final. That was his best Grand Slam run.

The reward of a likely meeting with Federer is a double-edged sword but the reigning champion's meeting with Mario Ancic is no foregone conclusion, even though the young Croatian is nursing an injured leg and still feeling his way after illness and a shoulder problem. But Ancic, who is also studying law with a view to his life after tennis, likes the grass and was, famously, the last man to beat Federer at Wimbledon before the number one's five-year winning spree.

"I haven't thought about Federer for one second," he said after beating Fernando Verdasco. Little doubt he was busy rectifying that on yesterday's day off.

"I think we are both six years better," said Ancic. "I was the up-and-coming top-10 player who was struggling at Grand Slams. I think the year after he won Wimbledon he exploded and today he is a completely different player. I mean we've played three or four times after that. He beat me."

Five times, actually, since the 2002 win. Ancic knows the difficulty.

The bottom half of the draw showcases Raphael Nadal and Andy Murray. The Scott has momentum but meets Nadal in imperious form. Murray's win over Richard Gasquet was of a different order from what he needs to do to beat Nadal, who has, arguably, been playing with more control, precision and power than Federer over the past eight days.

Nadal has met Murray three times, twice last year and again in Hamburg prior to Roland Garros 2008, where the Spaniard won 6-3, 6-2. But it is their meeting at last year's Australian Open that Murray draws on for confidence. The Scot took Nadal to five sets in the fourth round, having briefly held a 2-1 lead. He was then blown away in the final two sets, 6-3, 6-1.

"I learnt that I could obviously play with him, play at his level" said Murray. "For probably four-and-a-half sets I was up there with him and definitely had my chances. I think both our games have changed since then. He's definitely playing better on grass than he has in previous years. I like to think I'm playing a bit better."

The two have minor problems, Murray the effects of a four-hour match and Nadal a leg problem after he heard a crack behind his knee as he slid for a ball against Mikhail Youzhny.

"I obviously would like to have won a bit quicker," said Murray of his five-set match. "I'm gonna try and recover real well, make sure I get enough food in me, enough sleep, try and prepare the best I can. Obviously he's the favourite for the match. But you know I do think I could win that."

The other pairing in the bottom side of the draw pits 32-year-old Rainer Schüttler against Arnaud Clément, who entered for the Shelbourne Irish Open just in case he fell during first week at Wimbledon. It's a given neither man can believe he is still in the frame and facing a possible semi-final meeting with Murray or Nadal.