Dani Alves faces a fight to be full fit for the World Cup after damaging his knee ligament.
The Brazilian defender was taken off after picking up a blow as Paris Saint-Germain won the French Cup.
And Alves, 35, is facing a minimum of three weeks out, with the Samba Stars reporting for training on May 21.
A spokesman told ESPN Brasil: “Following Daniel Alves’ right knee injury, which occurred yesterday during the French Cup final, the tests performed today showed a high detachment of the anterior cruciate ligament with posterolateral sprain.
“His condition requires a minimum of three weeks of care before re-evaluation.”
Tite picks his squad for the tournament on Monday, with Alves likely to be included in the hope his recovery goes as scheduled.
The Selecao will meet in Brazil before facing Croatia and Austria in friendlies on June 3 and June 10.
They begin their campaign against Switzerland on June 17 and are among the favourites for glory.
Brazil’s hopes have been boosted by Neymar ditching his crutches to go for a bike ride.
Alves’ PSG team-mate is on the mend after breaking his foot, with a summer Real Madrid move on the cards.