Andy Murray continued his pursuit of a second major title in 2016 to go along with a Rio Gold medal. But after an epic five-set battle, it was Kei Nishikori coming out on top 1-6, 6-4, 4-6, 6-1, 7-5 in a tug-of-war match that kept the New York crowd on the edge of their seats.

The two players traded big strikes from the baseline early in the first set, but Murray found the first opening with a break of Nishikori’s serve to go to 3-1. Murray would continue the same high-level of play that he exhibited against Grigor Dimitrov in the previous round, frustrating the Japan native.  With nearly flawless groundstrokes, Murray forced Nishikori into high risk shots and with it came 14 unforced errors in the set as the Scot cruised.

In the second set, it looked like more of the same as Murray garnered an early service break. However, the six-seed began to confidently, and aggressively control more points. He would break back and after a delay to close the Ashe Stadium roof, he forced Murray to serve to stay in the set at 4-5. And in this all important game, Nishikori struck a series of tremendous groundstrokes to gain an advantage, break the Murray serve, and even the match.

In the third set, the level of play and intensity rose as each player immediately exchanged service breaks. The two competitors traded punches throughout the set, which produced some compelling shot making and defensive prowess. But it was Murray who found the additional service break and closed out the set.

However, Murray couldn’t carry the momentum in the fourth set as he clearly became mentally frazzled. During a break point, the Ashe PA system blared mid-point forcing the chair umpire to call a let point. Murray took umbrage with the decision by Umpire Marija Cicak. Afterward, he had a difficult time finding his focus and lost his rhythm. Nishikori held serve and immediately broke Murray to gain control of the set.

A now-confident Nishikori quickly struck in the fifth set, gaining a service break.  But Murray, pumping himself up, fought back and appeared to regain control in a match full of ebbs and flows. However, Nishikori would step up his game once more with angled groundstrokes and well placed drop shots. But after a series of high intensity games, the two top-ten players evenly battled down the stretch. Finally, the Japan star broke Murray to gain a 6-5 edge. He was able to shake off any nerves and served out the match.

“It was so exciting on the court but I tried to stay calm. It was really tough,” said Nishikori afterward. “He's a great returner, there were lots of up and downs. I didn't start well.” However, he finished well and will return to the semifinals after having advanced to the finals in 2014.

Nishikori will face the winner of the Stan Wawrinka – Juan Martin Del Potro match later in Arthur Ashe Stadium.