Real Madrid general manager Jorge Valdano claims the club have not yet finished in the transfer market this summer.
Los Merengues completed the signing of defender Ricardo Carvalho from Chelsea for £6.7million on Thursday, as the Portuguese centre-back links up with Jose Mourinho once again.
The 'Special One' has already added Sami Khedira, Pedro Leon, Angel di Maria and Sergio Canales to his squad so far, and Carvalho becomes the latest piece in the jigsaw.
Madrid have also been linked with Germany midfielder Mesut Ozil, while squad players such as Lassana Diarra may now be surplus to requirements.
"We are comfortable with the team that we have, but the exits and arrivals might not be over," said Valdano.
"There could be new signings and the club are open to all different possibilities but I can't name more possibilities in regards to who."
Meanwhile, new signing Carvalho says he is pleased to be reunited with Mourinho following his move.
The centre-back joins the Madrid revolution as Mourinho looks to take the Primera Liga title off rivals Barcelona in his first season in charge.
Carvalho, 32, reveals that the Portuguese coach tried to sign him last summer when he was manager of Inter Milan, and is happy to link up with him once more.
"Mourinho and I have won many titles together and I hope to continue that run with this club. He has won titles wherever he has been," he said.
"For the most part, I've had a good relationship with him. There have been one or two moments when it hasn't been. Now the relationship is good and I hope that it continues to be good.
"Jose is our manager and he has achieved success at every club he has worked at and I hope that continues. He loves to win and only wants to win.
"I have wanted to play here for a long time and finally, I'm here. Now I want to do everything I can to help Real Madrid achieve their objectives."