London, 5 July 2012 | AAP

Promising all-out attack, Roger Federer will shoot for the lines in a daring bid to break Novak Djokovic’s Grand Slam dominance in Friday’s high-stakes Wimbledon semifinal.

Djokovic has conquered Federer in four of their past five meetings at the majors, on hard courts in Melbourne and New York and on clay in last month’s French Open semifinals.

Even Federer concedes “slight” favouritism to Djokovic and says the Serb’s string of successes – including twice from multiple match points down – must only have strengthened the world No.1’s mental resolve.

Tellingly, though, of 26 previous match-ups, this will be the two tennis titans’ first career encounter on grass and Federer is vowing to seize on the subtleties of his most profitable surface to bring the Serbian powerhouse unstuck.

Djokovic these days ranks ahead of even the great Rafael Nadal as the most supreme defensive player in the game, but Federer believes the neutralising grass may diminish the top seed’s potent counter-attack.

“It’s much harder to defend on grass time and time again than on any other surface,” Federer said after delivering a fittingly royal quarterfinal display in front of Prince William and the Duchess of Cambridge.

“It’s hard to set up sometimes. It’s unusual, maybe [because of] the ball coming flatter at you.

“We’re used to playing with much more topspin and giving ourselves margin over the net, but then also into the court at the back.

“Whereas on grass, I think it’s worth it to go closer to the lines, use a lot of the down-the-line shots, which aren’t easier to pull off on other surfaces.”

With seven finals appearances at the All England Club to Djokovic’s one, the six-time champion also feels he holds a vital edge in experience on tennis’s most hallowed court.

“I honestly do believe I can play my very best on centre court at Wimbledon,” he said.

“It’s a question of confidence and a question of playing a lot of tennis on grass over the years for me.

“I think I’ve played over 100 matches on grass now, so I know how it works.

“It is obviously slowing down, but I still believe the aggressive player can be rewarded if he plays the right way.”

Djokovic admits the surface favours Federer, but maintains he too carries the required self-belief to keep his ageing challenger at bay once more.

“I improved playing on grass in the last couple of years. I mean, I won the title here last year,” he said.

“Got to another semifinal this year, so I’m feeling good about this surface, about myself on the court.

“I really have nothing to lose. I’m going to try to win.”

But should Federer win, and then equal Pete Sampras’s seven titles at the All England Club, the 30-year-old Swiss would also supplant Djokovic as world No.1 and match Sampras’s all-time record of 286 total weeks atop the rankings.

“Obviously it’s a big deal – no denying,” Federer said.

The victor will take on Britain’s great hope, fourth seed Andy Murray, or French fifth seed Jo-Wilfried Tsonga in the title match.

Murray, a three-time Grand Slam runner-up, advanced to his fourth consecutive Wimbledon semifinal with a spirited 6-7(5) 7-6(6) 6-4 7-6(4) victory over Spanish fifth seed David Ferrer.

Tsonga, the 2008 Australian Open runner-up to Djokovic, outclassed German Philipp Kohlschreiber 7-6(5) 4-6 7-6(3) 6-2 to reach back-to-back semifinals at London’s SW19.