Porto coach Andre Villas-Boas is to join Chelsea following the sacking of Carlo Ancelotti in May.
The 33-year-old Portuguese, who has worked with ex-Chelsea boss Jose Mourinho, guided Porto to the Europa League title last season.
The Portuguese club also clinched a domestic double, winning the league and the league cup.
Guus Hiddink has also been linked with a return to Chelsea, where he won the FA Cup as a caretaker manager in 2009.
Neither Chelsea nor Porto have made an official statement about the future of Villas-Boas.
