Chelsea have signed Nuno Morais, who was with Portuguese Second Division club Penafiel last season.
Mourinho has signed another of his Portuguese countrymen
The 20-year-old, who can play in defence or midfield, has signed a three-year contract following a successful trial at Stamford Bridge.
He joins Tiago, Ricardo Carvalho, Paulo Ferreira and boss Jose Mourinho among the Portuguese contingent at the club.
Mourinho, who was impressed by Morais' versatility, moved to sign him before the transfer window closes on Tuesday.