Nadal also struggled in the early going of his quarterfinal match on Wednesday against American Sam Querrey before finding a higher gear to win 7-5, 6-2, 6-2, reports Efe news.
With his 100th match victory at the Wimbledon, the most he has recorded at any of the four Grand Slam tournaments, 37-year-old Federer set up the dream contest once more against Nadal that fans have been waiting for ever since the draw was unveiled.
Ahead of that contest, Federer told the media he expected a different match than the ones they played at Wimbledon more than a decade ago. Last month the two met in another epic clash at the Roland Garros, where the Spaniard defeated the Swiss veteran.
"(He has) improved so much over the years on this surface. He's playing also very different than he used to. We haven't played each other in a long, long time on this surface. He's serving way different. I remember back in the day how he used to serve, and now how much bigger he's serving, how much faster he finishes points," the Swiss said.
When Federer and Nadal meet in Friday's match, it will be their first match at Wimbledon since the 2008 final, when the Spaniard held off a thrilling comeback by the Swiss to win 6-4, 6-4, 6-7 (5-7), 6-7 (8-10), 9-7.
That contest was the longest final ever at Wimbledon and considering the occasion and the pedigree of the two competitors is widely considered the greatest match in tennis history.
Prior to that match-up, Federer winner of a record eight Wimbledon men's singles titles had defeated Nadal in the 2006 and 2007 finals at the All England Club.
The legendary status of Federer and Nadal has only increased since 2008, with the Swiss now holding the record for most Grand Slam men's singles titles with 20 and the Spaniard currently in second place all time with 18.
The winner of the Federer-Nadal blockbuster though may not even be the favourite in Sunday's final.
Serbian world No. 1 Novak Djokovic was in sublime form in brushing aside Belgium's David Goffin on Wednesday and will be the heavy favourite when he takes on Spain's Roberto Bautista-Agut in Friday's other men's singles semifinal.
( With inputs from IANS )