LONDON -- Like the patch of scorched earth around the baselines of Centre Court, Roger Federer's nearly 35-year-old body isn't quite what it used to be.
Thirteen years ago, he won his first Grand Slam singles title here at the All England Club, and then, nine years later, his most recent. In the four years since, Federer's has become increasingly fragile, at times even brittle, despite reaching the final here the past two years.
With a berth in Friday's semifinals (8 a.m. ET on ESPN/WatchESPN) secure after a soaring two-sets-to-love comeback against Marin Cilic, it's easy to forget that Federer is coming off his first missed major since 1999. He underwent knee surgery in February, a career first, and an uncooperative back forced him to sit out Roland Garros.
Against Cilic, the No. 3 seed somehow got better as the match, his first five-setter in nearly two years, progressed. In typical Federer fashion, he was fascinated by the challenge.
"What I like about being in a fifth set is you actually get really tested to see where is your fitness, where is your mind at," Federer said afterward. "Can your shoulder, your back, your legs -- can they sustain 3 hours, 17 [minutes] of just hitting big serves, running, being explosive.
"Can it handle it? That's why I was very intrigued, pushing myself a lot in the fifth to get over the finish line because I was feeling as good at the end as I was in the beginning. That gives me, I think, a lot of confidence moving forward from here."
Forward translates to a date with No. 6 seed Milos Raonic, a classic confrontation between an aging champion and an ascendant, possible future champion. At 25, Raonic is nearly a decade younger and has a big game that is highly conducive to grass. On Wednesday, Raonic dismissed American Sam Querrey, who earlier knocked No. 1 Novak Djokovic out of the tournament to destroy the Serb's dream of a calendar Slam.
Raonic, 6-foot-5 with an enormous wingspan, has always had a big serve and forehand. He has 114 aces for the fortnight, tied with John Isner, who lost in the third round, for most in the tournament. Federer, by comparison, is at 65.
Since Raonic brought John McEnroe into his coaching circle before the French Open, the Canadian has been more aggressive, working his way toward the net when he can. Some here have made comparisons to Pete Sampras.
"That was a part of the motivation to bring [McEnroe] along to help, was to improve that aspect of how much I can implement it in my game and how to use it and what the right moments are," Raonic said.
Two years ago here, Federer drilled Raonic in a drama-free 6-4, 6-4, 6-4 semifinal. But earlier this year in Brisbane, Australia, Raonic won by the same count but in two sets.
"I look forward to it a lot," Raonic said. "Definitely a great opportunity. Two years have passed since I played him here in the semifinals. I'm happy that I have another shot at him. One thing, I'll probably look at that one from the beginning of this year, what I did well. Probably from the mental side, I'll look at what I wouldn't want to repeat from two years ago."
Raonic insisted he is now better-equipped to win the Grand Slam that many have predicted for him.
"Definitely mentally, physically," he said. "I think from every aspect, I've improved. I know how to sort of turn things around to get them on my terms. And then when things aren't going well, I know what things to look for to change.
"I came here with a simple goal for this tournament. I think everybody on my team has that same objective. I think that's why John was willing to join, for that same goal."
That goal is to win the tournament. Federer, of course, is thinking the same thing.
It was fitting that the signature win over Cilic was Federer's 307th in a Grand Slam singles match. That would be one more than Martina Navratilova's total of 306, the previous record for Grand Slam victories.
"Funny, people were rubbing it in my face on Twitter and stuff," the 18-time Grand Slam champion Navratilova said Wednesday. "I didn't even know what the number was until I saw all that. Now it's a different measuring stick. Slams get all the glory.
"The important records to me now are nine Wimbledon titles, 74 matches in row, 80 tournaments winning singles and doubles same event."
Federer's not quite there, yet, but eight Wimbledon titles would be a men's record.
"Today was epic," Federer said, understandably sounding a bit giddy. "Probably going to look back at this as being a great, great match that I played in my career, on Centre Court here at Wimbledon. This is huge for me, my season, my career. I'm very, very happy.
"The record -- I'm not even quite sure what we're talking about, but I'm sure it's great, I don't know."