Nick Kyrgios has refused to be too critical of his own performance after losing to Andy Murray in the first round of the US Open.

Third seed Murray ensured that he avoided a shock defeat by progressing with a 7-5 6-3 4-6 6-1 at Flushing Meadows, but Kyrgios believes that he can be happy with his display despite seeing his hopes ended at the first hurdle.

"I thought I put in a really good performance tonight. Obviously it's not the result I wanted. But I thought I was focused and ready for today. I had a good preparation," he told the tournament's official website.

"I thought I played well. I created opportunities. I didn't serve my best; yet I still put myself in some winning positions. I just didn't come away with the win."

Murray will meet Adrian Mannarino in the second round.