Fonseca won the Next Gen ATP Finals – for the best male players aged 21 and under – at the end of 2024.

He was the second-youngest champion at the tournament after world number one Jannik Sinner, who won in 2019, and who persuaded Fonseca to turn professional after a hitting session in 2023.

Fonseca then began the year by stunning ninth seed Andrey Rublev in the first round of the Australian Open, with Spain’s four-time Grand Slam champion Alcaraz tipping him as a future star.

Against Cerundolo, he came back from an early break down in the first set to take the lead and served for the match at 5-4 and 6-5 up in the second.

He was twice broken back by his experienced opponent, but Fonseca took total control in the tie-break, dropping just one point before clinching the title with an angled forehand winner.

He will rise to 68 in the world rankings before travelling to his home tournament, the Rio Open, which begins on Monday.