Rodrigo Taddei, the Roma midfield player, believes it will require an extraordinary effort to turn around their Champions League quarter-final tie with Manchester United.

Roma arrive in Manchester desperate to overturn a two-goal first-leg deficit, and despite Sir Alex Ferguson's side being the overwhelming favourites to progress to the last four, Taddei says that Roma are only focused on victory tomorrow.

"Those of us who have come to Manchester have to be focused and try to give not 100 per cent but 200 per cent in order for us to progress, something which is our aim," Taddei said. "We are aware of how difficult our task will be. We have a negative result against us and we face a great side away from home."

However, Roma's hopes of progressing to the semi-finals have been dented by the withdrawal of Francesco Totti. The talismanic forward has not travelled with the squad after failing to recover from a thigh injury that kept him out of the first leg defeat in Rome. And while Taddei admits the captain will be sorely missed, he believes the squad can still produce the result they need.

"Totti is a top player and this cannot be denied," Taddei said. "But we have had to play without him already this campaign and we have taken important results.

"It is understandable that others may find in Totti's absence an excuse for defeat," he added. "But we know that the defeat against Manchester United in the opening leg came from the fact we didn't make use of our chances to score."

Roma will also be without Matteo Ferrari, who underwent knee surgery earlier this month.