Roger Federer stands just two wins away from a record eighth Wimbledon title but faces a perilous trip through the land of the giants if he is to become the tournament's oldest champion.
The 35-year-old Swiss has defied time and logic to reach a 12th semi-final at the All England Club where he will face Tomas Berdych, the 2010 runner-up, on Friday.
If he gets past the Czech for the 19th time in 25 meetings, Federer will face either Sam Querrey or Marin Cilic in Sunday's final.
The contrast between the 18-time Grand Slam title winner and the other three contenders could not be more stark.
Federer stands 6ft 1in (1.85m) and weighs in at 187lbs (85kg); Berdych is 6ft 5ins (1.95m) and 200 lbs (91kg).
Querrey and Cilic tower over him at 6ft 6ins (1.97m) and 210lbs (95kg) and 196lbs (89kg) respectively.
Federer, bidding to reach an 11th final at Wimbledon, is therefore aware of the physical threats posed by his rivals.
"All three guys are taller and stronger than I am," said Federer.
"I've got to figure out a different way, carve my way through somehow with my slice and my spins, my consistency.
"Being the favourite or not the favourite doesn't matter. These other guys are all big hitters. I feel like they will have their say in the outcome of the matches.
"They've got big serves, big forehands, they are big hitters."
Federer has made the semi-finals without dropping a set and has been broken just three times.
He even managed to match Milos Raonic -- who boasts the second fastest serve of the tournament at a blistering 142mph (228.5km/h) -- with 11 aces in his quarter-final victory.
Federer is the second oldest semi-finalist after Ken Rosewall who finished runner-up in 1974 at the age of 39.
He is also the overwhelming favourite after 'Big Four' rivals Andy Murray and Novak Djokovic suffered injury-hit exits on Wednesday and Rafael Nadal lost in the last 16.
Federer is reaping the rewards of pruning his schedule with Wimbledon just his seventh event of 2017.
He skipped the 2016 and 2017 French Opens which were won by Djokovic and Nadal.
After losing to Raonic in the Wimbledon semi-finals last year, he shut down his season to rest a knee injury which had already required surgery earlier in 2016.
He came back in January this year, won the Australian Open for his 18th Slam, added the Indian Wells-Miami Masters double before hibernating again through the clay court season.
"I'm playing very well. I'm rested. I'm fresh. I'm confident," added Federer.
Berdych, meanwhile, will not be overawed by facing Federer having defeated him in four sets in the 2010 quarter-finals on his way to his only appearance in a Slam final.
Four years younger, 11th-seeded Berdych came to Wimbledon ranked outside the top 10 for the first time since 2009.
He knocked out eighth-seeded Dominic Thiem in five sets in the last 16 before seeing Djokovic retire with a right elbow injury in their quarter-final.
Berdych is in the Wimbledon semi-finals for the second successive season after a poor year at the Slams in which he exited the Australian Open in the third round and Roland Garros after two matches.
"Roger is an exceptional tennis player, he's the greatest of them all. It's a great challenge to have the opportunity to play him," said the 31-year-old.
Querrey, meanwhile, has reached a maiden semi-final at the majors at the 42nd time of asking.
The 24th-seeded American, who knocked out 2015 champion Djokovic 12 months ago, proved that was no fluke by downing defending champion Murray in the quarter-finals on Wednesday.
The 29-year-old is also the first American man to reach a Grand Slam semi-final since Andy Roddick reached the Wimbledon final in 2009.
Querrey trails 2014 US Open champion and seventh seed Marin Cilic 4-0 in head-to-head meetings.
Two of those clashes have been at Wimbledon -- in 2009 and 2012.
The encounter five years ago was the second longest match in Wimbledon history at five hours and 31 minutes, something Cilic doesn't want to experience again on Friday.
"Hopefully it's not the longest one ever," he said of a match decided 17-15 in the final set.
However, with Querrey and Cilic having fired 231 aces between them at the tournament, a long afternoon cannot be ruled out.