Stanislas Wawrinka defeated world No. 1 Rafael Nadal on Sunday to win the Australian Open, becoming the first man outside the Big Four of Nadal, Novak Djokovic, Andy Murray, and Roger Federer to win a grand slam since 2009. Despite winning his maiden grand slam, the win was significantly overshadowed by the theater that unraveled on Rod Laver Arena. Taking their seats before the match commenced, the crowd could not have been prepared for what lay ahead in Rod Laver Arena.

Wawrinka hadn’t won a set off Nadal in any of their past 12 matches, and few expected the Swiss to wrestle a set away from the Spaniard, let alone win the match. But from the outset, Wawrinka was superb. His game plan was simple, and he executed it with flawless accuracy. His tactics on serve and his variation against Nadal’s lethal groundstrokes were impressive as he found a way to hit past the world No. 1. Serving and volleying as well as stroking majestic backhand winners at will, Wawrinka never relented in outhitting the Spaniard. In his first grand slam final, it would have seemed predictable for Wawrinka to spend five or six games feeling Nadal out and relieving the inevitable grand slam final nerves. But that was the opposite of what happened as Wawrinka channeled his nerves for the better, exploding out of the blocks and breaking Nadal in the fourth game of the set.

Wawrinka had undoubtedly done his homework on the Spaniard in the lead-up to the match. Nadal had struggled against the deep cross-court backhand from Grigor Dimitrov in his quarterfinal, and this weakness was again exposed by the ruthless, hard-hitting Wawrinka, who hit the ball as crisply as he’d done all tournament. After taking the first set in just 37 minutes, one couldn’t help but feel that Nadal was lacking something in his game. Whether it was his movement or his ball timing, his groundstrokes appeared labored at times and he struggled hitting through the ball.

After Wawrinka won the first set and then broke Nadal in the first game of the second, the crowd started to sense something was amiss. Their worst fears were confirmed when Nadal called for a medical timeout and it became obvious that his back was the problem. His return to the court was met with jeers from the crowd, who did little to endear themselves to Nadal or the rest of the world. As play commenced, it was clear that Nadal was less than 50 percent fit and would struggle to continue, let alone make a contest. He continued to receive treatment on changeovers as his first serve at times failed to reach above 75 mph. It was a visibly distressed Nadal, often staring at his team acknowledging his pain. At times it was difficult to watch, but after 75 minutes Wawrinka had won two sets and was on his way to a career-defining victory.

However in the game of tennis, it is often said that it is easier to play a full-strength opponent playing their best than it is to play an injured opponent who has little to give. This could not be more true of the third set as Wawrinka’s level dropped and his game fell away, making numerous unforced errors and losing his rhythm. Struggling to find the focus to remain on task, Wawrinka surrendered the third set to Nadal in 38 minutes.

While the match score was two sets to one, Nadal never appeared to have the physical capacity to challenge for the match after clearly injuring himself at the beginning of the match. He had lost the ability to serve with any menace or chase down balls.

In a match where much will be made of Nadal’s injury in the wash-up, it was important for Wawrinka to have the last say, and he did on match point as he blazed a forehand crosscourt winner to seal the four-set win in two hours and 21 minutes. It was a marginally restricted celebration by the Swiss as he raised his arms in triumph before consoling a desolate Nadal.

The world No. 1 was inconsolable as he attempted to explain what happened to him in the match in the post-match press conference. “Since the beginning I felt a little twinge in my back from the warm-up,” Nadal said with tears welling from his eyes. “It was a little bit worse in the first set. At the end of the first set, I started to feel worse. At the beginning of the second, during a serve in a bad movement was the key moment that I felt very stiff, very bad.”

A devastated Nadal also attempted to explain his emotional state after he mentally ruled himself out of the match after the first set. “During the whole year you are working for a moment like this, and it arrives. But the moment it arrives, you feel that you are not able to play at your best,” he reflected.

Despite his injury, he wanted to keep the focus on Wawrinka. “This is not the real moment to talk about (the injury). It’s the moment to congratulate Stan,” he said. “He's playing unbelievable. He really deserved to win that title. I’m very happy for him. He's a great, great guy. He's a good friend of mine and I am really happy for him.”

Nothing could remove the smile from a usually shy Wawrinka. “It's quite crazy what's happening right now” an ecstatic Wawrinka said.  “I never expected to win a Grand Slam. I never even dreamt about that because for me, I was never good enough to beat those guys.”

Wawrinka also said once he knew that Nadal was injured, it was difficult for him mentally. “I had to stay calm with myself just to try to stay aggressive because he was injured. But he was still trying a little bit. It was not easy,” Wawrinka said while maintaining an ear-to-ear grin. “I started to get really nervous because I started to realize that I could win a Grand Slam. So it wasn't easy. But at the end I just came back to the game and focused on what I wanted to do.”

And despite the injury to his opponent, Wawrinka was proud to have played so well and close out the match. “To beat Rafa today, even if he was injured, I think I played my best first set during the match,” he said. “I was ready to play four hours or five to beat Novak in the quarters, to beat Berdych in the semis. That shows me I'm doing the right thing after many years. If you practice well, if you work hard, you will always have a chance to be in a great position to play your best tennis.”

So as the lights on Rod Laver Arena go dim and the final fan leaves Melbourne Park, the Australian Open ends for another year. Although many would have scoffed at anyone who suggested that Wawrinka and indeed China’s Li would win their respective singles crowns, it’s satisfying to acknowledge that the world of tennis will continue to evolve and eventually produce grand slam winners from countries not known for tennis, such as perhaps Dominika Cibulkova’s Slovakia. It is also satisfying to recognize that any player, no matter their origins or career history, has a chance to succeed on the biggest stage, giving the game that we love a never-ending sense of unpredictability.