Cilic starts well, with deep penetrating cross court shots off of both wings, pushing Nishikori back and rushing the fastest hands in tennis. After holding, the break comes off of two forced errors on the backhand wing - a rarity for Nishikori, who is yet to impose himself on any point in the match. The Cilic serve is as good as it had been this entire tournament, whereas Nishikori's as inconsistent as it's been throughout the week.
Up until the 5th game Nishikori didn't hit a single clean winner until an inside out forehand in a neutral rally, followed by an ace up the T in the deuce court. On the strength of this momentum Nishikori gets three break points - the first he misses a forehand up the line, the second an ace up the T and the third a missed backhand up the line. Cilic then closes it out with a backhand up the line - the same one that Nishikori missed three points earlier.
In the subsequent game Nishikori goes up 30-0, then dumps another backhand in the net and a double fault before finishing the game off with a service winner. At 2-5, serving to stay in the set, Nishikori hits two forehand winners that wakes up his many supporters in the crowd - evidenced by a smattering of Rising Sun flags throughout the stadium. After a double fault at 40-15, he holds to force Cilic to serve it out. Cilic duly complies with two service winners, including one on a 116mph second serve to the forehand, which he has targeted whenever he needs a point.
Nishikori starts the second set missing a flat serve up the T by 6 feet, then getting burned on the second. He follows it up with an ace and an unforced error before holding comfortably with a forced error and a one-two combination of the serve and a cross court forehand winner. Cilic responds with another hard serve wide in the deuce court, for which Nishikori still has not found an answer. But finally, after imposing himself with the backhand, Nishikori breaks and the crows erupts as much in support of a good match as support for Kei. He nearly gives the break it right back in the subsequent service game, but he dealt with the break point with an ace wide in the deuce court, and a forced error on game point. At which point he calls the trainer and gets a medical time out to get work done on his right leg, abdominals and back. He is up 3-0.
The match is a study in contrasts that makes tennis an exceptional sport. Cilic is 6'6" with a huge serve and long languid strokes off both wings. His racquet is heavier and he uses it to produce flat penetrating strokes that elicit more errors than he produces winners. By contrast, Nishikori's feet are almost as quick as his hands, which produce enormous racquet head speed, spin and disguise: the direction is so difficult to read. Ironically, Kei produces more winners precisely because he defends better and hits with more spin.
Cilic puts up a good fight in the fifth game, down a second break, and burns one up the line two points in a row - the first a backhand winner, the second a backhand setting up a winning backhand angled volley. Nishikori is a deceptively good volleyer, with above average hands, which he uses more for disguise and racquet head speed. He finishes the game with a backhand up the line off a half volley and is up 5-0. At this point Cilic would do well to hold, if for nothing else, to force Nishikori to serve it out, and if he does, Cilic then serves first in the 3rd set.
But Nishikori makes a bid for the bagel, with heavy returns of Cilic's second serve, whose speed is now down below 100mph (whereas in the first set it topped out at up to 116mph). Nishikori holds a shaky one to finish off the set, including a very heavy inside out forehand winner to put Cilic out of his misery, but he serves first in the third.
Cilic finds the wide serve in the deuce court again on the first point followed by an approach to net and a half volley winner. After an error in the ad court, a carbon copy of the first point results in an error on the volley. The next point Cilic wins by hanging on and defending the net well - off of a weak volley that lands just inside no man's land, Nishikori outwits himself and tries to hit behind Cilic cross court, but Cilic holds his ground and wins the point. A loose error on a short forehand he tried to play inside out, and a deep backhand Nishikori placed in the corner that he thought was going out costs Cilic the break. Nishikori resolutely consolidates before Cilic finally breaks the momentum with a gritty hold. Nishikori replies with a workmanlike hold of his own.
At 1-3 Cilic now needs to hold to stave off the prospect of another breadstick, and starts with two service winners. Kei fights back with yet another pair of blistering forehands - the first a cross court pass that buckles the racquet in Cilic's hands, the second a straight forehand up the line winner from the back court. If you look carefully the words "Citi Open" are tatooed on that line. Cilic holds to force his way back to relevancy with a hold. Nishikori asks for the trainer again, getting his right wrist re-taped, which is disconcerting because an injury to that wrist kept him out of the game for a year. It doesn't appear to be affecting him, however, immediately winning long exchanges and hitting an ace before holding after targeting first the forehand on each serve. Nishikori has just refused to concede the baseline since the start of the second set, and Cilic is forced to defend, which is a weakness in his game. Nishikori then challenges on a wide ace at 15-15 that is reversed and Kei wins the point on another inside out forehand. Cilic stays strong with second serves above 100 and holds for 3-4.
Cilic then turns up the heat with a couple of blistering forehands and a Nishikori double that gives the big Croat the break he needs to even the match. In the words of John Newcombe, this is sweaty palms time for him now. After winning 10 out of the last 12 games, and well into cruise control mode, unless he can break back, he will be on the verge of giving it all away if he can't handle the scoreboard pressure. Nishikori challenges another huge forehand from Cilic that appeared to skid through the line - it was out. He then elicits an error, and hits the line off his own big forehand to break Cilic right back despite his challenge of a Nishikori backhand up the line - it was flush on the line.
Kei is now serving for it and after Cilic pushes a neutral backhand wide, he gets to 15-all with a deep backhand up the line that rushes Kei into an error. He tried to repeat the feat on the next point, dumping it in the net, before putting yet another neutral cross court shot out of bounds (this one a forehand) to bring up two match points.
Up 40-15, Nishikori experiences a rush of blood to the head, and belts an inside out forehand 6 feet over the baseline. He then closes out the match with a service winner to the Cilic backhand.