Nishikori wasted no time in getting himself ahead in the match, breaking Golubev at the first time of asking having taken his opening service game to 30.
From that point on in the first set the Japanese was clinical, taking another three of his four break points on the way to a 6-0 win in just 28 minutes.
Golubev battled back in the second set and broke his opponent in the first game before doing the same again for 3-0. However, he was broken back for 3-1 and then again to level the set at 4-4.
Nishikori then ramped up the pressure once more to claim the final two games of the set and book his place in the fourth round.