Joao Fonseca currently has a question mark hanging over him according to seven-time Grand Slam champion Mats Wilander.
Fonseca enjoyed a breakout season in 2025, which saw him win two ATP titles and climb over 100 places in the rankings.
As a result of the Brazilian teenager’s success last year, Fonseca has been backed to challenge Carlos Alcaraz and Jannik Sinner.
However, after Fonseca lost in the first round of the Australian Open, Wilander has raised his concerns over the 18-year-old.
Mats Wilander raises concern he currently has over Joao Fonseca
“Latin America didn’t lose talent, it lost structure. Fewer tournaments, less investment, less continuity,” Wilander told CLAY and RG Media.
“João Fonseca could be a turning point: technically, he has it all. The big question mark is his physical condition. But for the region to truly make a comeback, one star is not enough: systems are needed.”
Fonseca had been struggling with a back injury leading up to the Australian Open this year, which forced him to withdraw from tournaments in Brisbane and Adelaide.
However, the 19-year-old still decided to play the Australian Open, before losing in the first round of a Grand Slam for the first time in his career.
More concerns were raised over Fonseca following the Australian Open as training footage surfaced of him, but the world number 33 is now set to make his return to the match court.
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Who could stop Joao Fonseca defending his title at the Argentina Open?
Fonseca won the Argentina Open last year as his first ever ATP title, and he is now set to return to Buenos Aires as the defending champion.
As the third seed at this year’s tournament, Fonseca will receive an automatic bye to the second round where he will play either former top 20 player Alejandro Tabilo or former Argentina Open champion Facundo Diaz Acosta.
Where do you think Joao Fonseca will be ranked at the end of the 2026 season?
Some of the other threats in Fonseca’s half of the draw include top seed Francisco Cerundolo, Tomas Martin Etcheverry and Matteo Berrettini.
| Argentina Open 2026 | Joao Fonseca’s Potential Opponent |
| First Round | Receives a bye as the third seed |
| Second Round | Alejandro Tabilo/Facundo Diaz Acosta |
| Quarterfinal | Tomas Martin Etcheverry (7)/Laslo Djere/Roman Andres Burruchaga/Andrea Pellegrino |
| Semifinal | Francisco Cerundolo (1)/Matteo Berrettini (8)/Damir Dzumhur/Vit Kopriva |
| Final | Luciano Darderi (2)/Sebastian Baez (4)/Daniel Altmaier (5)/Camilo Ugo Carabelli (6) |
While Fonseca has the pressure of being defending champion, he does not have the pressure of defending points as they have already been taken from him in the latest ATP rankings update.
Fonseca will be looking to gain his points, form and fitness back when he starts his campaign in Buenos Aires on either Wednesday or Thursday.
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