Brighton manager Roberto De Zerbi has admitted Brighton will lose midfielders Moises Caicedo and Alexis Mac Allister this summer.
Both players are attracting interest from Chelsea ahead of the summer transfer window.
De Zerbi told Sky Sports: “We are working to become a big team. We are not a big team yet but if you want to compete with a big team like Arsenal and qualify for Europe, we have to progress our mentality.
“The players are the most important thing. I’m lucky to have players at this level. I’m working to give them my ideas and mentality but without good players you can’t achieve these results.
“We will lose some players, maybe Caicedo or maybe Mac Allister. We need to bring in some other good players. For Mitoma and Estupinan, they need to stay with us I don’t know if they are ready to play with big teams. You have to be ready in the head and we can offer them the chance to improve.”