Maresca reviewed their winter market campaign, while also confirming a long-term injury for striker Marc Guiu.
He said, "Marc unfortunately has a bad injury.
"It looks a long injury. Exactly how long, I don't know. Weeks or months.
Nico (Jackson) is better. Could be a risk (for Brighton), but it doesn't look like a long injury.
"Before the last game, we had two strikers, Nico and Marc, sometimes with Christo (Nkunku) there. In case they are both out, we will find some different solutions."
On their January market, Maresca said: "We did all the things we need in terms of players we need to leave and players we wanted. We did everything we needed.
"We were sure before the transfer window that Christo was one of the players we intended to keep."
On Joao Felix's loan move to AC Milan, Maresca also said: "Nothing happened. Players want to play all of the games but unfortunately they can't all play.
"He never complained. He was professional. We need defensive balance and when you have so many attacking players, you can concede transitions and I don't like that."