Roma head coach Luciano Spalletti has conceded that he has asked his side "to do the impossible" when they take on Real Madrid in the Champions League tomorrow night.

The Italians go into the clash at the Bernabeu as big outsiders to progress through to the quarter-finals thanks to the 2-0 deficit that was inflicted upon them on their own patch three weeks ago.

"I'm asking my team to do the impossible. The way they are training allows me to ask that question," Spalletti told reporters.

"We have to score early then we'll see what happens - it could change the balance of the tie, especially mentally.

"We must not be weak mentally and play to lose. If anyone thinks like that with me, they won't even train."

Roma won 2-1 on their last visit to Madrid in 2008.