Manchester United manager Sir Alex Ferguson has one eye on Sunday's Barclays Premier League derby clash against champions and neighbours City as he prepares for the meeting with CFR Cluj at Old Trafford.
With United already assured of progression from the group stages, it is preserving and perhaps extending their three-point lead in the league that is of greater importance to the manager.
And those hopes are likely to rest on a much-improved defensive showing after their 4-3 win at Reading.
United have now conceded 32 goals this season, something Ferguson knows they must improve on.
``It is a worry,'' said Ferguson.
``If we perform like that on Sunday then God knows what's going to happen to us.
``We've lost 32 goals already - I can't remember us losing so many goals before Christmas.
``Saturday was like Cartoon Cavalcade and when you see City have Balotelli, Dzeko - really tall players - it's going to be a big challenge.
``It's a concern. But that's on Sunday. It's five days away but at this moment in time it feels like five months.''
It had been suggested that Nemanja Vidic could be ready to play either on Wednesday or by Sunday, but Ferguson has suggested the Serbian centre-back will miss both matches.
``I don't think Nemanja will play,'' said Ferguson.
``He feels he needs another few days' training so he won't be available.
``He's not far away. He's training well now but I think another few days will bring him on better.
``But if he doesn't play against Cluj there's no chance he'll play in the derby game, although I wasn't considering Nemanja for Sunday anyway.''
For Cluj, the highlight of this visit could be for goalkeeper Mario Felgueiras, who finally gets the chance to emulate his former Sporting Lisbon team-mate Nani by appearing on the Old Trafford stage.
The pair were colleagues in the Sporting youth team and visited one of the world's most famous grounds as part of a short trip to England during their schoolboy days.
For Nani, it proved to be a visit to the ground he would eventually call home as he followed the trail blazed by Cristiano Ronaldo.
It has taken Felgueiras slightly longer.
But the 25-year-old is delighted to have finally made his own journey.
``When I was at Sporting, I came to visit the stadium in pre-season,'' he said.
``When you are young you talk about the dreams you have when you are older. Coming back on a regular basis was one of them.
``Only Nani did it, but I am happy for him. He got the opportunity.
``I have not kept in touch. Since he played with me at Sporting he has confirmed what a good player he is, who made a difference for Manchester United a lot of times.''
Felgueiras might be kept busy as Cluj look for the win that would force Galatasaray to claim victory in Braga to seal their own last-16 berth.
Nevertheless, as Cluj already have a Europa League place to look forward to next spring no matter what the outcome, new coach Paulo Sergio feels expectations have already been exceeded.
``No-one bet on us to even reach the Europa League,'' he said. ``We have achieved a great deal to get this far.
``But we can't afford to lose our focus. If we spend any time wondering about things we can't do anything about, there is a chance we will lose control of our work.
``It is possible we would only beat Manchester United once if we played them 15 times.
``But that one night could be tomorrow (Wednesday).''