Wayne Rooney scored the only goal of the game as Torres was booked for diving.
The Chelsea striker, signed from Liverpool in the January transfer window, has now played more than 10 hours of football without a goal.
Asked why Ancelotti kept Torres on for the entire match and substituted Didier Drogba for Nicolas Anelka, Ancelotti said: "We have to have confidence. He (Torres) has to have confidence and keep going and he'll score.
"I wanted to play differently. Drogba worked very hard in this game after playing 90 minutes on Saturday, so for this reason I kept Torres on the pitch."
Source: PA
Source: PA