Controversial Australian youngster Nick Kyrgios defended his on-court antics after bowing out of the US Open in the first round on Tuesday.

Kyrgios was accounted for by British third seed and close friend Andy Murray 7-5 6-3 4-6 6-1 at Flushing Meadows in New York.

The 20-year-old's erratic play was on show throughout at Arthur Ashe Stadium, with the maligned Aussie showcasing his tremendous potential, only to produce moments of unnecessary high-risk shots.

Tuesday's post-match media conference, however, was dominated by questions regarding Kyrgios and his on-court sledge of Stan Wawrinka at the Rogers Cup in Montreal last month.

The ATP handed Kyrgios $35,000 worth of fines for his "banged your girlfriend" remark, and any further indiscretions will result in a 28-day ban from tour events.

Asked by reporters whether he will grow up from his recent experiences, Kyrgios replied: "I think I'm on the right path. I don't think any of us in this room right now were perfect at 20. Speak up if you were.

"I'd like to think that I'm going to learn from it. I think I have."

Kyrgios' stock has plummeted following the well-publicised sledge in Montreal, with world number one Novak Djokovic and 14-time grand slam winner Rafael Nadal quick to condemn the youngster's actions.

However, Kyrgios denied the ongoing scrutiny had taken its toll against 2012 US Open champion Murray.

"I wouldn't say so much tonight. I thought I've been dealing with that pretty well," Kyrgios added.

"Obviously it's been tough. But I think I've moved on from it.

"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.

"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."