Ronaldo might be benched against Celtic as Carlos Tevez and Anderson are back in contention after missing Saturday's 4-0 win over West Bromwich Albion.
Paul Scholes, Owen Hargreaves and Michael Carrick miss out of course and they are joined in the stands by Patrice Evra who was taken off with a hamstring injury against West Brom and won't be risked tomorrow night.
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Nani scored Manchester United's third goal as they knocked Middlesbrough out of the Carling Cup.
Sir Alex Ferguson has backed his Manchester United side to bounce back from their Premier League defeat at Liverpool.
The first World Cup qualifiers in Europe brought mixed fortunes for United's internationals. Wayne Rooney was on the winning side after 90 minutes in an England shirt, thanks to two goals from Chelsea's Joe Cole against Andorra.
Manchester United have named their former midfielder Mike Phelan as assistant manager, while Rene Meulensteen becomes first team coach.
Phelan, 45, replaces Carlos Queiroz, who left his position to take over as Portugal's coach in July.
Dutchman Meulensteen is promoted from technical skills development officer.
Manchester United failed to become the ninth British winners of the Uefa Super Cup when they lost narrowly 2-1 to an impressive Zenit St Petersburg in Monaco.
For the first 60 minutes Zenit were comfortably two goals ahead through a fist half header from Pogrebnyak then a wonderful solo effort from Portuguese star Danny on 58 minutes.
Sir Alex has taken a 19-man squad to Monaco for Friday night’s Super Cup clash with Zenit St Petersburg.
The Reds left Manchester Airport on Thursday morning at 09:00 BST and will train at Stade de Louis II later in the day. Kick-off on Friday night is at 19:45 BST.
Manchester United winger Nani feels in good nick after featuring in Portugal's 5-0 victory over the Faroe Islands last night.
Nani missed United's 1-1 draw with Newcastle on Sunday, but said: "It was very good. We have shown willingness to win. That is what the coach asked from us. He told us to be focused and I think we were.
"I want to improve my form.
He may not be the new England captain but Rio Ferdinand will line up for his country tonight as Fabio Cappello’s side host Czech Republic at Wembley (20:00 BST).
John Terry was handed the armband yesterday, while Ferdinand was given the vice-captain role ahead of England’s 2012 World Cup qualifying campaign.