Juve are eager to close a deal for the Frenchman, who himself wants to see the move happen.
However, Palace are proving stubborn in negotiations and Juve are prepared to look elsewhere if nothing can be agreed today.
Il Corriere dello Sport says Palace want at least €30m to sell Mateta this month. However, Juve are insisting on a loan-to-buy arrangement.
For the moment, talks are at deadlock, though Mateta has now verbally made a transfer request - without giving formal written notice to Palace.
Along with Juve, watching in the background are Aston Villa, though player's preference is a departure for Turin.
If nothing can be agreed, Juve will switch their sights to Fenerbahce striker Youssef En-Nesyri, who is also interesting Villa and Serie A rivals Napoli.