The four players in question are: Marcos Llorente, Achraf Lazar, Luca Zidane and Isco.
It appears that Real Madrid's stars of the future are all already in place at the Bernabeu, but in some cases, the club must act quickly in order to make sure that several important pieces of the puzzle do not slip through their fingers.
That's because as many as four players could walk away from the club for nothing next summer if they aren't tied down to new deals.
The situation regarding Isco is by far the most worrying for Real, especially given his red-hot form of late.
Despite the former Malaga man having said himself on several occasions that everything is very close to being done, there has still been no official announcement and until there has been, Real fans will continue to worry.
It is thought that there is a new five-year contract in the offing for the Spanish international, which would tie him to the club until 2022.
Marcos Llorente is another who is highly-rated in the Spanish capital, but 'Fichajes.com' claims that he is not prepared to put pen to paper until he knows what role his will play in the Real squad.
The aforementioned source also reports that the situations regarding Zidane and Hakimi are uncertain but that there are likely to be movements on that front in the near future.