Crystal Palace duo Tyrick Mitchell and Michael Olise are both available for today’s FA Cup semi-final clash with Chelsea.
The Eagles pair had been fitness doubts for the game at Wembley but Mitchell starts and Olise is named on the bench.
Olise suffered a foot injury while away on international duty with France’s Under-21s last month and missed the 3-0 win over Arsenal and the 2-1 defeat against Leicester.
Mitchell, meanwhile, was substituted in the first half of that loss at the King Power Stadium with a calf issue.
Vieira said on Friday: "Tyrick [Mitchell] and Michael [Olise] have had some individual training and a little more today. We have to wait until tomorrow but they’ll only get involved if they're 100 per cent fit.”
Palace will be without Conor Gallagher, who is ineligible to face his parent club. Chelsea rejected a request from Palace to allow the midfielder to play at Wembley. In his place, James McArthur sits alongside Cheikhou Kouyata in midfield.
Vieira said: “The frustration is more for Conor. He played every single round, he has been doing really well, and not having the opportunity to be on the field and have this experience is something that he will miss.
“But we knew that playing Chelsea would mean Conor would not take part. Missing Conor will give other players an opportunity to step into the team.”
Starting Crystal Palace XI (4-2-3-1): Butland; Ward, Andersen, Guehi, Mitchell; Kouyate, McArthur; Eze, Schlupp, Zaha; Mateta.
