It was a match that was played at such a high-level throughout four sets, but in that fourth set, it had looked like Rafael Nadal had tweaked something in his leg. The tweak clearly bothered him not just for the fourth set but for the short fifth set as well. 

Nadal tried to serve just once in the fifth set to see how he would hold up, but Marin Cilic broke for a 2-0 lead as the world number one called it quits after as he frustratingly walked over to the chair umpire and then his bench.

This is Nadal's second ever retirement in a Grand Slam match. Cilic, who won 3-6, 6-3, 6-7(5), 6-2, 2-0, will now play Kyle Edmund for a spot in the Australian Open final. 

High-Level First Two Sets

The tone was set early on between the two as there were little margins to start the opening set. Nadal was the first to get a break point opportunities in the sixth game. Errors from the top seed allowed Cilic to hold for three-all. Nadal saved a break point in his next service game and saw his trademark fist pump, holding for 4-3.

An error-strewn game from the sixth seed saw Nadal with the first break of serve in the match, and the world number one made no mistake in closing out the first set with a forehand.

Quick holds for both men started the second set before battling through some long service games. Nadal grabbed the edge for a 3-2 lead on a double-fault from Cilic. Another deuce game between the two saw Cilic this time getting the break with a clean forehand winner. 

The sixth seed was all over the Nadal second serve this set as the Spaniard only won 25 percent of those points. An unretrievable cross-court forehand gave Cilic a second break in the set and an opportunity to serve out for the set. The Croat finished the set on a roll, winning four straight games.

Cilic was fired up to level the match at a set all (Mark Kolbe/Getty Images)
Cilic was fired up to level the match at a set all (Mark Kolbe/Getty Images)

Nadal Wins Thrilling Third Set

After the first couple of sets saw some error-filled games and break points, the third provided something different. Both men were rolling quickly through their service games, and Cilic's long forehand set up set point for Nadal. A powerful backhand from the 2014 US Open champion saved the set point and held for five-all. 

The tiebreak saw some momentum swings throughout. A cross-court forehand pass followed by a backhand winner put Cilic firmly in control, serving up 4-1. He gave the mini-breaks right back with an unforced error and brilliant return from Nadal. The returner won seven of the eight opening points as the Croat's forehand winner put him up 5-3. 

The turning point in the tiebreaker was at five-all. Cilic was in control of the point and went for the forehand winner but just slightly missed it. That gave Nadal a set point, and the Spaniard made no mistake in closing it out. 

Nadal went two sets to one up after a tremendous comeback in the tiebreak (Icon Sportswire/Getty Images)
Nadal went two sets to one up after a tremendous comeback in the tiebreak (Icon Sportswire/Getty Images)

Cilic's Level Too High As Hurt Nadal Ends Early

Many thought Cilic was unlucky to have lost that third set, outplaying Nadal for the most part, but as per usual, the Spaniard, always found a way to get through. The high-level play from the Croat continued with a strong backhand setting up break point. Right on cue, Cilic's forehand found the corner of the court for the break and quickly held for a 4-1 lead.

On the changeover, Nadal called for the trainer as it looked like he tweaked something in his leg. The trainer massaged Nadal's calf as the world number one said, "Now I feel a little bit tired and a bit of a strain."

Nadal getting checked out by the trainer (Michael Dodge/Getty Images)
Nadal getting checked out by the trainer (Michael Dodge/Getty Images)

Right after the change, Cilic set up three break points. With every ounce of effort, Nadal was able to save all three, battling to 2-4. The injury of Nadal put a damper on the set, but that did not stop the Croat from firing away to close things out at 6-2.

Despite the injury, Nadal wanted to give it a go in the fifth, to the respect of Cilic and the fans, and it was something that he would do because of his never-ending fighting spirit. The Croat went out quickly to hold as Nadal tried to serve to determine how he would deal with the rest of the set.

He saved three break points from 0-40 down and saved two more before getting a game point. His backhand went well wide on the game point, and Cilic converted on his sixth try to get the break. After that break, the world number one walked over to the chair umpire and shook his hand before embracing Cilic. 

The moment Nadal called it quits, walking over to the chair umpire for only his second ever retirement in a Grand Slam match (Clive Brunskill/Getty Images)
The moment Nadal called it quits, walking over to the chair umpire for only his second ever retirement in a Grand Slam match (Clive Brunskill/Getty Images)