How much of an impact will the dramatic nature of the victory over Aston Villa have on tonight's match?

I think it will have a massive effect. Straight after the final whistle on Sunday, Gary Neville said that he felt it had revitalised the team and given them a real lift going into the final part of the season. That probably tells you how desperate they were becoming on Sunday after two games without a win.

Sometimes a victory like that means so much more than just another win. The dramatic nature of that victory will mean that it is more than just three points in terms of United's season. I expect the impact that it will have had on the players will be clear to see tonight, especially given the number of players they were missing on Sunday.

Defensively, United have looked very shaky recently. But with Nemanja Vidic and possibly Rio Ferdinand to return tonight do you expect them to have a much more solid look about them?

I would expect so. The defence that they had on Sunday was very weak. Gary Neville, who is still a great player, hadn't played for two months and was badly exposed. They really struggled against Villa as they had in their previous two matches against Liverpool and Fulham so it will be interesting to see how they do defensively tonight.

I think if you were the Porto coach looking at United's past few games I would feel that there were weaknesses there. Certainly I would target John O'Shea at right back and although Vidic is back from suspension, questions marks remain over his confidence. Will it have taken a slight knock? Is his aura of impregnability still there after being given the run-around by Fernando Torres. We'll have to wait and see.

I think there will be a feeling within the Porto team that United are not as an intimidating a proposition as they were when the draw was made.

Where do you expect tonight's match to be won and lost?

United will hope to defend properly and control the game in terms of keeping a clean sheet. Sir Alex Ferguson will hope to make things as comfortable as possible for the second leg, which won't be easy given Porto's home record.

When United prepare for the big matches they look to people like Wayne Rooney and Cristiano Ronaldo to step up their game and score the goals. Ronaldo has scored four in his past four games even though he hasn't been playing that well. Having said that, he is still a real threat and you imagine that he will be especially motivated playing against Portuguese opposition tonight.

Porto clearly aren't the side they were under Mourinho. What should we expect to see from them tonight?

They are a decent team, but everyone at United was pleased when they drew them, because they are generally thought to be the weakest of the teams left in the competition. That's not to say they are a bad team but Porto are possibly the weak link out of eight very strong sides left.

Their away record, particularly in England, is absolutely dire. I think they have lost 11 out of their 12 matches here. They lost 4-0 at Arsenal earlier this season, lost 4-1 at Liverpool last season so no, they don't have anything like the same look to them as they did under Mourinho.

The one thing in their favour is that they still have that formidable home record. So if they are still in the tie after tonight I think United will be very worried and for that reason Ferguson will be relieved that his team are going into this game full of confidence, rather than tentatively.

What about United's new hero Federico Macheda, what part do you expect him to play tonight?

Ferguson has said he will be on the bench, but I don't think he would have even made the squad if they had everyone fit. Sunday was an exception because of United's absentees.

Maybe we'll see him at some stage but I don't expect him to be a major player between now and the end of the season once United have all their strikers available. He came in and did fantastically well on Sunday, but I expect his education will continue in the reserves.

Do you expect United to adopt an adventurous approach tonight, or will they err on the side of caution?

United have become very good at knockout football in Europe again. They went through a stage, four or five years ago, where they barely won a knockout game in Europe. They struggled to find that tactical balance then, but they have mastered it now.

If players like Michael Carrick, Vidic, Ferdinand and Patrice Evra play like they have done for most of the season, as opposed to the way they have over the past three weeks, then you imagine United could be positive without being as susceptible to the counter-attack as they have been recently.

I think it will be a fairly close game. Ferguson has said he would like to take a two-goal lead to Portugal for the second leg and I can see that being the outcome.