New York, NY, USA, 31 August 2017 | Darren Walton (AAP)

Australian teenager Alex De Minaur is pledging to learn from a brutal first-round defeat at the US Open in New York.

The 18-year-old wildcard won only two of the last 16 games in a 6-4 6-1 6-1 loss to Austrian sixth seed Dominic Thiem.

Resuming their rain-interrupted first-round encounter, Thiem needed just 20 minutes to clean up De Minaur after leading 6-4 6-1 1-0 overnight.

“It was a pretty good experience, first time playing against a top-10 player,” De Minaur said.

“I feel like there’s a lot to learn from it. I’ve just got to get back on the practice court and improve a couple of things here and there.

“I definitely felt like there were chances. At 4-all, I had game points on my serve to go 5-4 and maybe put some pressure on him.

“It was disappointing, my level, in the second and third set. It felt like it dropped. But that’s something I’ve got to work on to be able to keep that high level the whole match.”

A Wimbledon junior runner-up last year and former boys’ semifinalist at Flushing Meadows, De Minaur has made promising strides in his transition to the senior ranks.

He has already cracked the world’s top 200 and hopes to finish the season close to the 150-mark.

Davis Cup captain Lleyton Hewitt has taken a keen interest in the youngster and is likely to take De Minaur to Brussels this month as a hitting partner for Australia’s World Group semifinal against Belgium.

“They’ve pretty much told me that I’ve got the level there to be competitive against these guys,” De Minaur said.

“It’s now all about sustaining this level the whole match. It’s a learning curve. I’ve got to make sure I learn from each one of these experiences and make sure I get better on court.

“But that’s the type of tennis I want to see myself playing, aggressive tennis taking the baseline and getting to the net.”