Joao Fonseca believes his eye-catching performances at the Australian Open are just the start as he aims for progression up the rankings.

The 18-year-old produced a stunning first-round victory over world number nine Andrey Rublev in the first round in Melbourne before losing in five sets to Lorenzo Sonego at the next stage.

Fonseca was playing in his first-ever main draw and says he has his eyes set on reaching the top.

"It's my dream to play on the tour, the real tour where the top 50 players play," he said.

"I'm excited to join the top 100, play the big tournaments, get my place in this environment, and keep working to go bigger, to have more.

"I think for me, the sky's the limit. You need to work more and more to reach your dream, which is to become number one."

Defeat to Sonego ended a run of 14 consecutive victories at all levels for the teenager, but he accepted his inexperience in five-set matches cost him.

Fonseca said: "I think today the experience of Lorenzo got the better of me.

"When you play five sets, it's different. They know better when to be intense. I need to work more to stay mentally focused during the whole match to be prepared for this.

"That is the big difference to play a grand slam."