WIMBLEDON, England—In the final game of his shocking, 7-6 (4), 7-6 (8), 6-4 upset of Rafael Nadal, who before today had reached the final in every event he’d played this year, Steve Darcis scampered toward the net to retrieve a volley. He did the same thing midway through the first set, when we were only beginning to see what game the Belgian would bring to SW19, but seconds later he was on the turf and Nadal had won the point. The same sequence played itself out in the second set, during a tiebreaker, after Darcis had let four set points slip by. Nadal earned his first set point when Darcis was again one with the grass.

But Darcis stayed on his feet this time, even though it looked like he was about to tumble once again. He also struck a running forehand winner that deflated any momentum Nadal had earned by winning the first point of a must-break game. The way Darcis was playing, though, it wouldn’t have surprised me if he struck that same winning shot while falling down.

Two points later—the final one earned with an ace, just like Lukas Rosol did in his second-round stunner of Nadal last year at Wimbledon—Darcis did his Czech contemporary one round better. He’s no stranger to first-round upsets at Wimbledon: Darcis defeated Tomas Berdych to open his Olympic Games last year. But this, obviously, is on a different level, even if we come to find out that Nadal was in some way not at 100 percent health. That’s a hard scenario to envision after watching the Spaniard comprehensively dominate the tour since Indian Wells, but Nadal gave a decidedly meek effort today, rarely invoking the fiery spirit we so often characterize with the 12-time Grand Slam champion. It’s something we’ll have to follow in the coming days; Nadal did not budge on the topic during a combative post-match presser.

What Nadal did give his opponent on No. 1 Court was a steady diet of short balls, which Darcis pummeled more often than not. From the first set, Nadal seemed on the defensive—Simon Barnes’ words on Rafa, which Steve Tignor pointed out this morning, had more merit than I’d imagined.

Nadal targeted Darcis’ one-handed backhand, a smart strategy, at times. But there was a problem: Nadal didn’t do it often enough, and Darcis’ one-hander was the shot of the match. He hit it through the court and kept Nadal on the move, and when Darcis decided to use the slice version, that was just as effective. Darcis’ command of his backhand was impeccable, able to change the variety seemingly mid-swing, and it kept Nadal guessing and out of rhythm. It also reset countless points when returning serve.

It all added up to Nadal surrendering nine break points in the first set, and when Darcis converted his first one at 5-5, it looked like he’d take an early, surprising lead in the match. But Darcis played a poor game thereafter, although the prevailing form of both players returned in the tiebreaker. The world No. 135 was up a set, but he still had to walk the Rafa tightrope twice more.

One of the major reasons Darcis was able to do so was because of a powerful, effective serve, an arrow most players who have beaten Nadal at majors have in their quiver. Darcis’ supply never ran out; he was relentless in his service games, most of which were over in a couple minutes or less. Nadal saw just seven break points on the day, converting two, the latter to take a 6-5 second-set lead. This is typically the time a top player asserts their authority on an upset-minded minnow, but Nadal never rose to such heights, playing a tepid game before a pivotal tiebreaker.

Yet again, the play from both men in the tiebreaker was an accurate reflection of their play throughout the day. Darcis continued to fire bullets, track most everything down, and benefit from some uncharacteristically poor shotmaking from Nadal. He took a 6-3 lead, but when a sky-high return from Nadal caught the baseline at 6-5, Darcis seemed surprised, and his forehand reply sailed long. Yet Nadal couldn’t take advantage. His next return drifted long, and despite saving a fourth set point and earning one of his own, was unable to take command of a set, let alone the match. The world No. 135 was up two sets, but we’ve seen comebacks from such perilous positions before, often from the Big Four.

But if you weren’t convinced that it was Darcis’ day after two sets, the very next game should have shifted your opinion. With Nadal serving to open the third set at 15-30, he was forced to hit a backhand lob, which looked certain to be heading wide on television. What did Darcis do? He took it out of air with a no-look backhand volley-smash. A point later, he was up a break, and like he did all day, never looked back.

IBM Stat of the Match:In a three-set match featuring two tiebreakers, it's as simple as winning the right points. Darcis did that, and won more of them than Nadal overall, 127 to 113.

IBM is a proud sponsor and official technology partner for Wimbledon. For more information on this match, including the Keys to the Match, visit IBM's SlamTracker.