The news will be a blow, but not a surprise to supporters of the club.
Mateta, since his remarkable upturn in form over the past 18 months, has always made clear his desire to play at the highest level and has aims of playing in the Champions League and representing France at the World Cup.
The 28-year-old’s World Cup dream, one that seemed distant before Glasner’s arrival at the club, is one that can be achieved now after making his senior debut in October while the frontman has scored in his last two appearances for Les Bleus.
Sources with knowledge of Mateta’s situation say the player is disappointed with the club’s attitude because it has not kept its promises in terms of a new contract, recruitment and ambition, with the forward keen on a new challenge.
The timing compounds a difficult period at Selhurst Park given Guehi’s departure, Glasner’s forthcoming exit and the FA Cup embarrassment.
Palace are also winless in 10 matches and are still without key right wing back Daniel Munoz who is injured while Daichi Kamada is also on the treatment table.
Ismaila Sarr, a key forward alongside Mateta in the Eagles attack, has missed nine games while he has been helping Senegal win the Africa Cup of Nations.
Mateta himself is playing through a knee injury but his track record of scoring in the Premier League will make him an attractive option to clubs.
Palace made a club record signing in bringing Brennan Johnson to south London early in January from Tottenham but will need to be active before the transfer window closes on 2 February if they are to turn around what has been a challenging start to the year.