WIMBLEDON, England—On Wednesday, Sergiy Stakhovsky did something no one expected: He became the first man in nine years to beat Roger Federer before the quarterfinals at a Grand Slam. On Friday, Stakhovsky turned around and did something that was as predictable as his previous result was shocking: He became the sixth straight man to beat Federer at a major and lose his next match. In doing so, the 27-year-old Ukrainian joins Jo-Wilfried Tsonga, Andy Murray, Tomas Berdych, Novak Djokovic, and Rafael Nadal as Fed-conquerors who could conquer no more.

Even though he’s no longer No. 1, and despite the fact that Nadal, Murray, and Djokovic have beaten him many times, there’s obviously still a special high that comes with beating Federer, especially on grass or hard courts—Murray, for all of his accomplishments, had never done it before at any major before this year’s Australian Open. The last time a player beat Federer at a Slam and won his next match was at the 2011 U.S. Open, when Djokovic hit the return heard round the world in the fifth set, and followed it up with a win over Nadal two days later. After that shot, I guess Djokovic felt like he could no wrong.

But what works for Novak Djokovic, world No. 1, isn’t necessarily going to work for Sergiy Stakhovsky, world No. 116. Against Federer, Stakhovsky had rushed the net with reckless (and skilled) abandon. As he said, that was his only chance. Yesterday, after losing to Jurgen Melzer, Stakhovsky admitted that he had gotten carried away with his success.

“In general, if I would say about my match,” Stakhovsky said of his loss to Melzer, “I think I just played stupid. It would be the exact word to show how I should not play Jurgen, and I should have realized that somewhere in the second set.”

Stakhovsky’s “stupidity,” according to him, was believing that just because something works against Federer, it’s going to work against everyone else, and that he was suddenly good enough to “bully” a higher-ranked player like Melzer.

“I got so blinded by the game I produced with Roger,” Stakhovsky said, “that I kept going with the same game against Jurgen, which was just not right....I should mix it up. I should never play the same shot against Jurgen. He was returning much better today than Roger.”

Asked if he recognized his mistake during the match, Stakhovsky said, “Usually I’m trying to recognize it while the game is still on. But today I was a bully. If I wanted to win, I had to change. But I didn’t do it because I didn’t think about it.”

This was Stakhovsky’s first career win over a Top 10 player—that’s a surprise to me, considering that he was runner-up to Andy Murray at the 2004 boys’ U.S. Open; he’s been a pro for 10 years; and he’s been ranked as high as No. 31. Stakhovsky said he was wholly unprepared for his experience as the unlikely protagonist of Black Wednesday.

“Everybody wanted a piece,” he said. After beating Federer, he hadn’t left the grounds until 4:00 or 5:00 the next morning. “I wasn't ready for such a turnover. Next time, if I’m able to produce such a result, beating a top player, I’ll be more prepared and I’ll know how to behave myself.

“The only thing you don’t want to happen is to lose next round,” said Stakhovsky, speaking for all one-shot upset artists everywhere, “and it’s actually what happened. Because you’re trying to avoid it, it always comes.”

Studies have shown that Americans confer automatic intelligence on anyone with a British accent (though the same studies have shown that this isn’t as true if the Americans in question have actually been to Great Britain). Maybe Stakhovsky’s British-inflected English scores him some points with reporters like me, but one thing is certain: The interview room at Wimbledon will miss him. I’m not sure I’ve heard a more concise, specific, and honest take on what went wrong from the loser of a tennis match than what Stakhovsky gave us yesterday. He was equally articulate in victory.

Over the last year or so, Stakhovsky has been better known for his work in the ATP’s leadership than he has for his play. As I wrote after his win over Federer, so far Stakhovsky, whose parents are professors and whose brother is a doctor, has taken on the role of critic—of everything from court speed to equal pay to umpire’s interpretations of ball marks on clay. He’s as aggressive in his off-court role as he is on it. I don’t agree with all of what he says along those lines, but I’d like to hear Stakhovsky talk about tennis more. In his brief time in the spotlight here, he was as compelling to listen to as he was to watch.

But that time is up. Stakhovsky’s 15 minutes lasted approximately 70 hours. Hopefully he’ll have a few more before he’s done, because his lean and wiry serve-and-volley game blew a breath of fresh air into Centre Court for a day. He played the role, as Jimmy Connors would say, of a stopper—a player who has enough game to take out a top seed, but who can’t put everything together again. No wonder Stakhovsky described his match against Federer as “magic.” The phenomenon of the stopper isn’t unique to Federer, of course; last year Lukas Rosol beat Nadal here and lost in the next round to Philipp Kohlschreiber in straight sets. This year, Steve Darcis beat Rafa and couldn’t even play his next match.

On the one hand, the stopper may defy logic: How can the quality of a player’s game swing so wildly from one match to the next? And it may be disappointing to see someone rise so high one day, only to fall back to earth the next. But that’s why the stopper is valuable: He’s a reminder that tennis isn’t logical, it isn’t cut and dry, it isn’t rigidly hierarchical from one day to the next. It’s a game of individual match-ups, where a player can, occasionally, be good enough to beat Roger Federer but not Jurgen Melzer. It’s a world where, every so often, a knight or a rook or a pawn can take a king. And that’s why we watch. The stopper tells us anything can happen.

But at the same time, he doesn’t offer chaos; knight remains knight, king remains king. Unless you’re a diehard fan of that particular upset artist, there's something reassuring about watching him return to earth. The stopper has given us a thrill by disturbing the regular order of things, but when it’s all over, he’s left our sense of the world and its rightful hierarchies intact.

When it was all over for Stakhovsky, he said that nothing can take his moment of magic away from him. No one can take away his gutsy fourth-set finish against Federer, his drop to the Centre Court grass afterward, or the autographs he obviously enjoyed signing as he walked off.

“If someone would ask me,” Stakhovsky said on Friday, “Would you rather beat Roger and lose in the next round, I would always take it.”