Patrick Vieira says his Crystal Palace side have been working on different systems for their Premier League clash against Chelsea on Saturday.
The Eagles will be without regular starter Conor Gallagher for the clash against his parent club, which has left Vieira with a midfield conundrum to solve.
The Frenchman has been boosted by the recent return of midfielders James McArthur and Cheikhou Kouyate to action, while Will Hughes has been deemed fit to play a part after coming off injured against Brentford last week.