It tells you something about the textured, 3-6, 6-4, 6-1 win by underdog Dominika Cibulkova over No. 3 seed Maria Sharapova in the fourth round of the Australian Open that it’s hard to pin down just what was most impressive about the diminutive winner’s triumph.

Was it Cibulkova’s unrelenting willingness to throw herself into the match, body and soul, point after point, game after game? The shockingly heavy weight of shot that she produced, rally after rally? The ability to maintain her composure and focus in the face of Sharapova’s wildly fluctuating game, or the fact that the No. 20 seed won 57 percent of the points when she was obliged to hit second serves?

In the end, the key appeared to be Cibulkova’s ability to stand up to one of the two most intimidating players on the WTA tour and, essentially, stare her down. That, despite the fact that Sharapova is a foot taller (she’s listed at 6’2”, and Cibulkova at an optimistic 5’3”), and her blood-curdling scream is twice as loud as Cibulkova’s desperate grunt.

Truth be told, Cibulkova has faced moments like this before and handled them pretty well on a number of occasions—some of them against the same opponent. She was 2-3 against Sharapova going in, and beat her with the loss of just two games at Roland Garros. But that was way back in 2009, and Sharapova had beaten her twice in the interim, although both were fairly close battles.

Sharapova certainly was aware of Cibulkova’s eagerness to mix it up with her and, just in case she wasn’t, the Slovak reminded her in so many words after her last win here, an astonishing 6-1, 6-0 beating inflicted on No. 16 seed Carla Suarez Navarro. Cibulkova had lost all of nine games in three matches that kept her on the court for a grand total of three hours and 33 minutes up to this point in the tournament. Sharapova, meanwhile, had toiled under that hot sun for more than seven hours to earn her place in the same flight.

All that may help explain why Sharapova started this match at her imposing, aggressive best. She must have felt an urgency to establish herself, especially after her last two ragged performances. She broke Cibulkova in the very first game, then held with an ace to lead 2-0. Cibulkova got on the board with a hold in the next game, and had two break points against Sharapova in the next game.

Cibulkova was robbed of an excellent service return on the first break point by a bad call that was reversed, but the replay was a service winner by Sharapova. Cibulkova made a backhand error to waste the second break point, and Sharapova went on to hold for 3-1. The missed opportunity loomed large when Sharapova, easily playing her best tennis of the tournament, broke Cibulkova for a second time two games later to lead 5-2.

But Cibulkova wouldn’t give up the set that easily, and breaking Sharapova in the next game must have helped her confidence; it certainly slowed the juggernaut. Still, Sharapova served out the set without drama—then abruptly seemed to forget the character of her opponent.

Cibulkova snapped to life in the first game of the second set, breaking Sharapova with the loss of just one point (the break point was a Sharapova double fault). In the blink of an eye, Cibulkova reeled off eight of 10 points to hold serve and build a 2-0 lead. She was off to the races, striking the ball with savage accuracy, while Sharapova had one of those cringe-worthy episodes that makes you wonder how someone so good can so often be so bad. The upshot was an astonishing turnaround that left Cibulkova serving at 5-0.

But Cibulkova wasn’t the only player out there who knew how to stop the bleeding. Sharapova worked her way back into the match, breaking for 5-1 with a massive cross-court forehand winner. She held, and then belted an inside-out forehand winner to break Cibulkova’s next serve: 5-3. A quick hold by Sharapova left Cibulkova still serving for the set but with no more wiggle room. But Cibulkova smartly played as if she were behind instead of ahead 5-4, and her bold shot-making won the set with ease.

At that point, we endured the kind of intermission that has become all too common on the WTA tour. Seemingly suffering from some sort of pulled muscle in her left hip, Sharapova was awarded a very leisurely 10-minute injury time-out. If she was also conveniently trying to re-compose herself for a final push, the strategy backfired. She was broken in the first game of the first set, thanks to a double-fault and a third-shot forehand error.

Some will certainly point to Sharapova’s injury as a mitigating factor in this match, but I think that’s just blowing smoke. Oh sure, there were close-ups of Sharapova’s agonized, lingering glances at her support team in the player box, as well as replays of her touching her hip, or seeming to pull up short after hitting a shot. But the reality is that if Sharapova injured herself, it may have been mostly because Cibulkova bombarded her so effectively and relentlessly.

That doesn’t demand an asterisk in the re-telling. Cibulkova made Sharapova run a lot more than was good for her, and the little dynamo with the extra-long racquet is extremely mobile and surprisingly strong. If you can make Sharapova hit one more shot than she feels comfortable having to hit, you’re in there with a chance.

Cibulkova held the second game of the final set to lead 2-0. Sharapova gamely fought off a pair of break points and held the next game, but by that time the handwriting on the wall was becoming more legible.

After a quick hold for 3-1, Cibulkova backed Sharapova into a corner again. Sharapova, who was growing more aggressive with each passing game, survived a break point. But Cibulkova earned another one, during which Sharapova gambled and made a strong attack on the net. Cibulkova smacked a sharply-angled forehand pass that presented Sharapova with a tricky, low forehand volley that she pushed into the net.

That break made it 4-1, and Cibulkova more or less sealed Sharapova’s fate with a follow-up hold, after which she broke her a final time in the two-hour and 11-minute match.

Stat of the Match: Sharapova made almost twice as many unforced errors as Cibulkova, 45 to 28, and it wasn’t because the latter was playing more conservatively.