The draw for the first knock-out round of the Champions League has left some British clubs facing tough matches.
Arsenal are up against reigning Champions League title-holders AC Milan and Liverpool were drawn with the current Serie A leaders Inter Milan.
Celtic are facing up to two matches against Spanish giants Barcelona, but Chelsea have it slightly easier after being drawn with Greek team Olympiacos.
Sir Alex Ferguson's Manchester United will play French side Lyon.
United's club secretary Ken Ramsden said Lyon will not be happy to have drawn the reigning Premier League champions.
He said: "They are one of the better teams but they won't be pleased getting us."
Arsenal's managing director Keith Edelman said they would have preferred an easier match than AC Milan.
He said: "We would have preferred an easier one at this stage but everyone will be looking forward to this tremendously."
Celtic v Barcelona
Lyon v Manchester United
Schalke v Porto
Liverpool v Inter Milan
Roma v Real Madrid
Arsenal v AC Milan
Olympiacos v Chelsea
Fenerbahce v Sevilla
And Liverpool chief executive Rick Parry said playing Inter Milan would be tough.
Parry said: "It's a long time since we played them, they are a very good team.
"It's going to be tough but there are no easy ones at this stage."