Good start for Marin.
“It wasn't easy to put him away,” Cilic said. “He's a great counterpuncher.”
Cilic, the first reigning US Open champion to play in the US capital since Andre Agassi in 2000, and second seed Nishikori each had first round byes and saw their matches pushed into the wee hours by a rain delay.
“It gives me more confidence,” Cilic said of his Grand Slam title.
“I'm sure it's going to give me more faith in my game. In this moment I'm very happy with my game.”