Superstar. Manchester United will need to combat the flair of Lionel Messi

Who will make the difference at Wembley tomorrow? James Toseland looks at Barcelona squad and decides three key men who could swing the game their way.

Victor Valdes: When Barcelona are at their best, Valdes is often forgotten. His route to international football has been barred by Iker Casillas in the Spanish goal but, as a Catalonian, Barcelona are his national team and he has the ability to match his desire.

Key man - Dani Alves: The Brazilian’s ability bombing forward will be a test for Manchester United’s defence as well as his class from free kicks, but he is more of a winger than a right back and if United’s midfield can catch him unaware, they will have a chance to get behind the Barca defence.

Gerard Pique: The Manchester United reject has made a name for himself at the Nou Camp and is now a European Champion and a World Cup winner. Pique is also a proven goalscorer at the other end if Barcelona are ever forced to win ugly.

Javier Mascherano: The former Liverpool man will be making his first Wembley appearance. Eric Abidal’s illness has moved him from midfield to the defence but his organisation at the back has been up to scratch. Nevertheless he is a makeshift centre back and is not a stranger to the dark arts as United players know - he was sent off against them playing for Liverpool.

Carles Puyol: The Barca captain is the Ryan Giggs of the Nou Camp. He has made the transition from centre half to left back but does not have the willingness to bomb forward like Alves. He will, however, be on hand to stop Nani. Team-mates have said that Puyol is English in his spirit which may work to Barcelona’s advantage at Wembley.

Sergio Busquets: Busquets’ international reputation has been hindered by his play-acting in the semi-final against Real Madrid but that does not change his ability. This youngster trains with Xavi and Iniesta every day and it is beginning to show for his team.

Key man - Xavi: If Michael Carrick needs a lesson in passing, he can look no further than is opposite number Xavi. Xavi has broken all records for number of passes and successful pass completion records, and Barcelona’s identity is because of Xavi’s game. When he is on form, Barcelona are unstoppable.

Andres Iniesta: Second only to Xavi in passing ability, Iniesta is another candidate for matchwinner. His technique is incredible and he also has the ability to score goals down the middle when David Villa drops off to the left, and at important times – as Chelsea fans know from 2009.

Pedro: A Barcelona product, Pedro has grown up with their flair football and it is all he knows. He is no doubt the weaker of the front three but he still has technique in front of goal and will be one to watch out for.

David Villa: A prolific goalscorer throughout his career. He is similar to Berbatov in that his ability is forgotten because of the players around him, but he still has that natural knack for goals. This his first season and he is settling into the Barcelona way of playing, but this game could be when he announces his arrival.

Key man - Lionel Messi: The best player in the world. The best thing about Messi is that none of his goals are twenty five yard screamers, but goals that show his pace, skill, passing ability and prowess in front of goal. He does it in the big games as shown by the semi-final, and he has done it to Manchester United before.

Eric Abidal: After recovering from cancer, an appearance from Abidal in the Champions League Final would do everything to personify football’s fighting spirit and his desire to win. He is an international left back who could give Barca yet another attacking option.

Ibrahim Affelay: The Dutchman is starting to make his mark in the blue and red shirt and made a big impression to set up Messi in the semi-final. He has bursts of energy that could hurt a tired Man United later on after 80 minutes of chasing the ball around.

Seydou Keita: The Mali midfielder is a natural replacement after the loss of Yaya Toure. He has the strength and power to command the midfield and allow the flair players to attack.

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