Clubs from the same association must not be drawn against each other, meaning Chelsea cannot play Arsenal. Teams that met in the group stage must also be kept apart. Group winners will be paired against the pool runners-up with the winners playing the first leg, scheduled for 22/23 February of their tie away. The return legs will be on 8/9 March. Here are the possible opponents for England's four remaining teams.
ARSENAL: Barcelona, Werder Bremen, Porto, Bayern Munich, Real Madrid.
CHELSEA: Barcelona, Werder Bremen, PSV, Bayern Munich, Real Madrid.
MAN UTD: AC Milan, Inter, Juventus, Bayer Leverkusen, Monaco.
LIVERPOOL: AC Milan, Inter, Juventus, Lyon, Bayer Leverkusen.