Andy Murray has praised his tactical nous after overcoming Grigor Dimitrov to reach his sixth US Open quarter-final at Flushing Meadows.
The world number two took just over two hours to seal a 6-1 6-2 6-2 triumph on the Arthur Ashe Court in New York.
The Scotsman, who won the Grand Slam title four years ago, will now face 2014 finalist Kei Nishikori in the final eight.
On his way to victory against Dimitrov, Murray hit his fastest ever serve at 141mph, but he does not expect to repeat that anytime soon.
"I served 145 in San Jose once, but the next day they recalibrated the gun because it was completely wrong," Murray said courtside. "I think I was lucky. I've never hit over 140 before. I don't expect to do it again.
"Tactically I played a good match. I served very well when I got behind, very few unforced errors. I enjoy it in here [on Arthur Ashe Court], fantastic atmosphere. Tonight is the first night it's been a little bit windy.
"Kei has been to the final here, we've had bunch of tough matches. I played a good match against him a few weeks ago [in the semi-finals of the Olympics] and I'll need to play like that again."
Murray could face Juan Martin del Potro or Stanislas Wawrinka in the semi-finals if he manages to get past Nishikori.