Montenegro managed to beat Wales 1-0 on Friday.
Roberts said: “Any optimism has gone within one game of our qualifying campaign. Toshack’s taken the players as far as he can.
“It’s time for a fresh voice and face.
“Giggs would be my choice – he would gain instant respect of the players and would inspire them.”
Giggs told News of the World recently: “My aim would be to manage either Manchester United or Wales.”
