Fonseca after his stunning victory over Rublev: "I knew I could beat him".

Joao Fonseca won the first Grand Slam match of his career on Tuesday, defeating No.9 seed Andrey Rublev in three sets.

On a run of 14 consecutive victories, the 18-year-old Brazilian continues to string together impressive performances.

In a press conference, he revealed that he had played this match without pressure:

"Everything was new for me, I wasn't the favorite. I went onto the court with this mentality of 'I'm an 18-year-old, he's a top-10 player'. I tried to do my best.

I knew I could beat him, but I didn't feel any pressure. When I was leading two sets to nothing, I started to think a bit more about winning the match, but I had to stay focused.

The nerves came, but I stayed mentally strong. I'm happy with the way I played today, but I'm concentrating on the next match.

That's the mindset of a champion, I'm just trying to focus on the next challenge."

Fonseca will face Lorenzo Sonego, who defeated Stan Wawrinka, in the 2nd round.