WATCH: It's been a shocking, thrilling, downright nutty week of tennis

February, generally speaking, is the slowest month on the tennis calendar. There’s an Australian Open hangover, and the two tours hover a bit under the radar in anticipation of Indian Wells and the Miami Open, which dominate the entirety of March.

This past week has been the exception to the rule. It’s been a brilliant, shocking week of tennis. Andy Murray and Novak Djokovic—the world’s top two male players—as well as Rafael Nadal, Roger Federer and Stan Wawrinka were in action, as were many other superstars. Of those five Grand Slam champions, only Murray and Nadal remain in their respective draws.

The madness began very early in the week, with Wawrinka’s loss to 77th-ranked Damir Dzumhur. If you can believe it, that was one of the more mundane happenings to occur at the Dubai Duty Free Tennis Championships.

Before heading to Acapulco, let’s stay in Dubai and take a look at an early contender for match of the year.

Evgeny Donskoy d. Roger Federer—3-6, 7-6 (7), 7-6 (5)

Federer came into this second-round encounter in Dubai on an eight-match winning streak to begin the year. He took the first set easily before proceeding to choke in three different instances. Donskoy, ranked 116th, saved three match points in the second set. In the decider, the 18-time Grand Slam champion led 5-2 and seemed to be on the verge of escaping a scare. But in keeping with the theme of this week, Donskoy came back to force a tiebreaker. Federer jumped out to a 5-1 lead, but Donskoy rattled off the next six points to complete one of the most improbable comebacks in recent memory.

Andy Murray d. Philipp Kohlschreiber—6-7 (4), 7-6 (18), 6-1

Murray came into this Dubai quarterfinal match riding fairly high. In his first tournament since crashing out in the fourth round of the Australian Open, the world No. 1 breezed through his first two opponents in routine fashion, without dropping a set. He had a far more difficult time with the 33-year-old German. Murray dropped the first set and was in serious trouble in the second. The two split the first 12 games of the second, which led to one of the most thrilling tiebreakers of the past decade. In the 31-minute, 6-second tiebreaker, Murray saved seven—seven!—match points before somehow, some way, taking it 20-18. The Scot refused to lose, exhibiting some of the best defense we’ve seen this season. In an anticlimactic third set, Murray breezed past a dejected Kohlschreiber to advance to the semifinals.

Nick Kyrgios d. Novak Djokovic—7-6 (9), 7-5

A night after coming back from a set down to oust Juan Martin del Potro, Djokovic was outclassed by Nick Kyrgios at the Abierto Mexicano Telcel in Acapulco. The polarizing Australian served masterfully against the world No. 2 to the tune of 25 aces—16 in the first set alone. Djokovic, facing Kyrgios for the first time, played the 21-year-old tough—the first-set tiebreaker was 11-9—but the world No. 17 was simply the better player on this night. After the match, a clearly frustrated Djokovic was in no mood to talk.