Juve are seeking to sign De Ligt for €70m.
Ajax have announced defender Matthijs De Ligt has been left out of their squad for their summer tour to Austria pending "a possible transfer".
The youngster's future has remained in the balance all summer as the likes of Manchester United, Barcelona and Paris Saint-Germain have all been heavily linked with an approach, but recent reports have indicated that Juventus are now in pole position to sign the starlet.
He scored the winning goal in Ajax's 2-1 win against Juventus in last season's Champions League quarter-final.
Journalist Mike Verweij of De Telegraaf now reports that an agreement has been reached between Juventus and Ajax with all the paperwork completed, meaning De Ligt will join Juventus.
De Ligt has agreed a reported deal worth £10.4m a season with Juve, who extended their record of successive Serie A titles to nine last season.
Sarri's side have already made six summer signings with Adrien Rabiot, Aaron Ramsey, Gianluigi Buffon, Luca Pellegrini and Merih Demiral all arriving, while Cristian Romero was purchased from Genoa before being loaned back.