Murray rallies for 4-set win in US Open quarters

And Murray wasn't exactly playing like an Olympic gold medalist.

Then the crowd started to filter in, the court started to slow down in cooling temperatures and — probably most importantly — Marin Cilic started to get tense. A point away from going down two sets, the third-seeded Brit rallied then rolled for a 3-6, 7-6 (4), 6-2, 6-0 victory Wednesday.

"He got nervous. That was the main difference," Murray said. "I did start playing better towards the end of the second set. And because I was in it, I started to feel that momentum was with me.

"It wasn't necessarily through my great play in the second set why I got back into it. But after that, I was hitting the ball much better, and I felt confident at the end of the match. I was returning well, serving well, and moved better at the end. It was good to finish like that, obviously."

A surprise finish in the next quarterfinal changed the terrain of Murray's road to a first career Grand Slam title. Peppered with questions about a potential rematch with Roger Federer during his news conference, Murray — who was sneaking glimpses of the score of Federer's matchup with Tomas Berdych — reminded everyone to respect the Czech.

He was right. Berdych upset Federer to become Murray's semifinal opponent.

Murray had trailed 5-1 in the second set before breaking twice to come all the way back. In the tiebreaker, Cilic had a 4-2 lead and a point on his serve. Murray erased the mini-break with an easy forehand passing shot, running off five straight points to even the match.

With royal in-law Pippa Middleton in the crowd, he won the last 11 games to wrap up the victory in 3 hours.

Cilic, seeded 12th, was seeking his first U.S. Open semifinal berth. The Croat had a set point at 5-2 in the second, but Murray hung in throughout a 14-shot rally and put the point away with a soft backhand volley into the open court.