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Luciano Spalletti has a full squad at his disposal for Zenit, with only Danny a long-term absentee, as he looks set to play a 4-3-3 formation with Hulk leading the line.
Massimiliano Allegri is unlikely to be able to select Robinho as the Brazilian picked up a thigh injury in training. Massimo Ambrosini could make his first Champions League appearance of the season.
Manchester City will be without David Silva, who has not recovered from the hamstring injury he picked up playing for Spain against France last week. Defender Vincent Kompany is suspended.
Real welcome Sami Khedira back into the squad after he missed the win over Celta Vigo because of a thigh strain. Defenders Alvaro Arbeloa, Marcelo and Fabio Coentrao remain sidelined.
Colombian striker James Rodriguez is expected to lead the line for Porto, with Steven Defour likely to return to the starting line-up.
PSG suffered further injury problems after their weekend clash with Reims, with forward Nene ruled out for the match. The Brazilian suffered a fractured cheekbone and is likely to be out for six weeks.
Defender Laurent Koscielny is set to return to the Arsenal squad after missing Saturday's defeat against Norwich with a back injury, but forward Alex Oxlade-Chamberlain misses out with the hip injury.
Montpellier will be without Karim Ait-Fana as he will be out for six months after injuring his right knee in training.