Richard the...Lion Hearted?

You never know who will surprise you. You never know who will revert to his former self. You never know when a routine day at a Grand Slam will turn into anything but.

Those were the lessons that we learned, not for the first or second or third time, as the sun set at Wimbledon on Wednesday. Until about 7 p.m. local time, this intermittently rainy day had gone entirely by the book, and it looked as if the men’s quarterfinals were going to end up being no match for the show that the women had put on 24 hours earlier. The world’s three best male players, Novak Djokovic, Roger Federer, and Andy Murray, had all won in straightforward fashion, without dropping a set or being forced to endure the indignity of playing a tiebreaker. The day’s liveliest topic of conversation revolved not around who was on the court, but who was in the commentary booth. Today was the day that Andy Roddick made his debut, long-awaited by many, with the BBC.

What about the world’s fourth-best player, Stan Wawrinka? The French Open champion hadn’t dropped a set all fortnight, and had been promoted by some into the ATP's most exclusive club of all, the Big 4. Whether Stan was a replacement for Rafael Nadal, or the name would soon be changed to the Big 5, was still under discussion in the bars and restaurants around the Wimbledon village. The one thing everyone knew was that Wawrinka had long ago distanced himself from his quarterfinal opponent, Richard Gasquet.

True, Wawrinka had lost the first set to Gasquet, but he had quickly righted the ship and won the next two. This was a guy, after all, who had won 13 of his last 14 matches; by now he had an ocean’s worth of confidence to draw on. Then something unexpected happened at 4-5 in the fourth set. After serving brilliantly for much of the afternoon—Wawrinka would finish with 22 aces—he double-faulted for the only time all day when he was set point down.

Was Wawrinka human? Was Stan still Stan, a man who had made it past the fourth round at Wimbledon just once in 10 tries? Card-carrying members of the Big 4, after all, don’t often double-fault to hand sets over to Gasquet—the Frenchman’s career record against Djokovic, Federer, Nadal, and Murray is 7-44. Was Wawrinka's widely presumed rematch with Djokovic going to have to wait?

Yes, it was. Wawrinka would lose the match, 6-4, 4-6, 3-6, 6-4, 11-9, though the defeat was less about his own poor play than it was the resolve of a man who has never been known for it. Coming in, the 20th-ranked Gasquet had lost 15 of his previous 16 matches to opponents in the Top 10. His last meeting with Wawrinka, at the 2013 French Open, had ended in heartbreak: After winning the first two sets in front of a roaring home audience, he had dropped the last three to the silent horror of that same audience, and lost 8-6 in the fifth.

For the first eight games of today’s fifth set, Gasquet played as if that match were a distant memory. He was the one who was seeing the ball well. He was the one who was reading his opponent's serve. He was the one doing the shotmaking from his backhand wing. As the set progressed, Gasquet, the game’s version of the Microwave, looked ready to go nuclear and start burning blind winners into the court as only he can. When Gasquet threaded a delicate running forehand up the line and past Wawrinka to break for 5-3, this fifth set had begun to resemble another that he had won, over Roddick, at Wimbledon eight years ago.

Then Gasquet gave it right back. Serving for the match at 5-3, his beautiful backhand suddenly turned ugly, and he was broken. The Microwave, it seemed, had shut down for the day. Wawrinka held for 5-5 and went up 0-30 on Gasquet’s serve; surely this was the end. Instead, the Frenchman dug in and found a way to hold.

“I had to fight, fight, to keep my serve,” Gasquet said. “It would have been tough for me to lose after being ahead 5-3.” It seems the fear of that loss, yet another tough loss, drove him.

The setting and the stakes drove both players. The match picked up speed as the two men barreled from 5-5 to 6-6 to 7-7 to 8-8 and beyond. Holds came quickly; Gasquet continued to construct points aggressively and Wawrinka continued to serve brilliantly. The light faded over No. 1 Court, but the winners, and the players, kept flying.

Finally, it was Wawrinka who blinked in that fading light. His confidence may have been high, but his full-throttle shots will always be risky, and at 9-10 he missed three in a row to go down 0-40. Then a Gasquet forehand clipped the top of the tape and fell backward, while a Wawrinka forehand did the same and went over the net. Now the score was 40-30. When Wawrinka drilled a first serve down the T, it looked as if another Gasquet chance had come and gone. This time, though, he reached out and stabbed a forehand return back into the corner, and watched as a Wawrinka backhand sailed long. This time, finally, luck was on Gasquet’s side.

Luck and something else: A player who has always won with natural talent won instead with grit. Gasquet isn’t a candidate, like his opponent, for the Big 4, but he’s the one going to the final four at Wimbledon.