Thomas Tuchel played an important role in convincing Saul Niguez to join Chelsea.

The Spain midfielder had spent his entire senior career at Atletico Madrid, making 340 appearances for the La Liga giants.

But he will now line-up for the Blues after completing a season-long loan move, with the west London club possessing an option to buy.

Goal reports Tuchel made a phone call to Saul and promised the Spaniard that he will be used solely as a central midfielder.

The 26-year-old grew frustrated at Atleti because Diego Simeone played him in a number of roles outside of his preferred position.

Saul has already been training with his new teammates during the international break and could be selected for his debut against Aston Villa on Saturday.