to keep an eye on Adriano and Zlatan Ibrahimovic when they face Inter Milan at the San Siro on Tuesday night.
Beckham, whose AC Milan team were beaten 2-1 by Inter in Serie A eight days ago, feels United will be favourites to go through to the quarter-finals of the Champions League if they can tame Inter's two strikers.
'They have got good players all the way through the squad, but I think the two forwards are strong,' he said, after playing 90 minutes in Milan's 1-0 win over Cagliari on Sunday.
Forward thinking: Adriano (left) and Ibrahimovic
'They are quick; they can hold the ball well and they are not frightened - so if you can control them, then you have got a chance.
'But Man Utd have also got players that can win games, and their defence is exceptional at the minute.'
Cup holders United will be in buoyant mood when they face Jose Mourinho's Inter, after opening up a seven-point lead at the top of the Barclays Premier League.
But their opponents lead Serie A by nine points and will be equally focused on this game, if not more so after failing to go beyond the quarter-finals in the last three years.
High hopes: Beckham can see United winning
But as far as Beckham is concerned, there can only be one winner over the two legs - the Red Devils.
'They are favourites in my eyes, but I'm biased,' said the former Old Trafford midfielder.
'I think they are because of the strength of their squad and the way they have been playing recently. They are on a run where they look unbeatable, and I hope that continues.
'As a Man United fan, I'm on their side - and also as a Milan player. I'll be coming to the game and I'm sure I'll speak to some of the players and the manager.
'I'm looking forward to it because they are two great teams, two great managers and they have got some great players in both teams - so it's going to be a great game.'
Beckham will be back at the San Siro again on Thursday night for the third time in five days, to appear for the Rossoneri in their UEFA Cup clash with Werder Bremen.
Victory in that game will be essential in dissipating the pressure which is mounting on Milan coach Carlo Ancelotti, and Beckham will do all he can to ensure he remains in charge.
'I am fortunate in that I had a great coach at United and I have got a great one here too with Ancelotti,' he said.
'He is very good with the players and enjoys huge levels of respect. I hope I can still play under him for a long time.'
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