Carlo Ancelotti backed striker Fernando Torres to come good after his Chelsea side lost their Champions League quarter-final first leg against Manchester United at Stamford Bridge.
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."
He added: "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."
Ancelotti believed his side were unlucky to lose and was furious with Spanish referee Alberto Mallenco for denying Chelsea what appeared an obvious penalty in injury time when Patrice Evra seemed to bring down Ramires.
Ancelotti said: "It was clear. For everyone. Everyone knows it was clear. The problem is I know it's sometimes not easy to give the penalty in the last minute and you need to have personality, courage and character. Not always do referees have these kind of skills.
"I'm disappointed but this is the result. Not just the referee, but the assistant was in the right position to decide that was a penalty. I said to the referee (after the game) that it was a penalty and he needed to whistle. He said nothing. No answer.
"The players are aggrieved. But we have to forget it and be focused for the next game. We have to try our best there."
Ancelotti insisted he would not rest players against Wigan in the Barclays Premier League at the weekend.
He said: "Our focus is to play against Wigan and to win, to take confidence and three points in the table. We don't have a problem physically. We'll have time to focus for the game at Old Trafford."