Toro Rosso have appointed former Manor team principal John Booth as director of racing on a consultancy basis.
Booth left Manor at the end of the 2015 Formula One season but the experienced Englishman has agreed to return to the paddock ahead of the Russian Grand Prix this weekend.
Toro Rosso team principal Franz Tost said: "I have known John for many years and I am delighted to welcome him to the team.
"Formula One is becoming ever more complex, with recent changes on the tyre front, car set-up, radio communications and so forth.
"Therefore, having a competitive car and talented drivers, both of which we have, on its own is not enough. With his vast experience I am sure John will help the team raise its game and become a more effective force over a race weekend."
Booth said: "It is a great honour to join such a well-established and competitive team as Scuderia Toro Rosso.
"It is a team that has achieved so much in a relatively short space of time. I am looking forward to getting started and working with Franz and the team this weekend in Sochi."