Lionel Messi acknowledges Manchester United threat

Messi expects a tough challenge at Wembley (AFP PHOTO/ JOSEP LAGO)

Lionel Messi expects a different Manchester United side to the one Barcelona beat in the Champions League final in 2009 as the two teams prepare to meet in the European showpiece at Wembley on Saturday night.

Messi scored the second goal in Rome as Barca beat United 2-0 to seal a treble of Primera Division, Copa del Rey and Champions League titles in coach Pep Guardiola's first season in charge.

"I have good memories of the final in Rome, but that's in the past," said Messi.

"All finals are different and this will be a totally different game to that one - United have changed (some of) their players and it will be different."

Messi also rejected claims the Red Devils are weaker than two years ago.

"They have their league and they are in the Champions League final," he said.

"They are not weak; they have very good players and a lot of quality up front - and they are used to winning."

Nevertheless, the Argentina forward believes Barca can exploit some weaknesses in Sir Alex Ferguson's side.

"I don't know how they will play but it will be a special game and we will look for their defects," he said.

In order to do so, Barca coach Guardiola has been studying videos of United - including the match in Rome in 2009.

"We watched that match yesterday and today," he said.

"They were better than us in the first half, even though Samuel (Eto'o) scored, they dominated and it was only in the second half that we were able to have some more chances."

And Guardiola admits he is envious at the strength in depth available to Ferguson.

"They can field four or five teams that are all competitive," he said.

"I went to watch them play Schalke (in the Champions League semi-final second leg at Old Trafford) and they made nine changes and still won easily.

"I can't make nine changes to my team because we have a small squad, but they have so much quality - (Dimitar) Berbatov, Chicharito (Javier Hernandez), (Wayne) Rooney, (Paul) Scholes, (Ryan) Giggs - they have so many players to choose from."