Deco fears Rafael Benitez's 'inside knowledge' could count against Barcelona when Liverpool travel to the Nou Camp for tonight's Champions League last-16 first-leg clash.
Benitez, a former Real Madrid youth coach and trophy-winning Valencia boss, has an intrinsic knowledge of Spanish football and will be relishing the chance to face Madrid's fierce rivals in such a high-profile clash.
And Brazilian-born playmaker Deco is well aware of the face.
'Liverpool will be a tough game and we are looking forward to it. Their coach and players know all about Spanish football and in Benitez they have a fine manager,' he said.
'I believe this is an advantage for Liverpool and a disadvantage for Barcelona. That is not to say we know nothing about Liverpool. I watch them on television a lot and they are strong, but Benitez has inside knowledge of all of our players.'
Deco, who also described Reds captain Steven Gerrard as 'the best player in the Premiership', expects a tough match against the Anfield outfit.
'We all know about the Champions League. Liverpool won the tournament before us, so we will be up against the previous champions. It will be winners against winners,' he said.
Portugal international Deco believes Liverpool are very difficult to beat and dismissed the notion that Barcelona are favourites to progress to the quarter-finals.
'There is no favourite for me. Liverpool are a strong side at home and will obviously try and win here to give themselves an advantage in the return match. Both teams have good managers and quality players. Each side is strong playing their own way and it will be a hard-fought series,' he said.
The double Champions League winner with Porto and Barcelona was sent off in Sunday's 2-1 Primera Liga defeat at Valencia.
The home side deployed a rigid counter-attacking style in that match and Deco sees some similarities in this Liverpool team.
'Perhaps defensively they are quite comparable, but Valencia are stronger on the counter-attack and maybe in the air, while Liverpool are very strong in midfield. We will have to work very hard in that area of the pitch,' he said.
Deco admits that Barcelona have not been at their best lately, but claims they are fully focused on beating Liverpool.
'It is not possible to play your best all the time but we will put all our energies into winning tomorrow. We are well motivated anyway and perhaps after losing that game (against Valencia), we will be more fired up,' he said.
The player also hopes his side can cut out the defensive errors they made in that match.
'Sometimes you do make mistakes. We make mistakes, like all teams. It is part of football. But we must be 100% concentrated,' he said.
Deco also believes that Argentinian midfielder Lionel Messi is returning at just the right time to help Barcelona.
'Leo is very motivated to play in this tournament. We are happy he is back with us. He is very important for us and there is no better time for him to return. We have missed him,' he said.
Despite Messi's return to fitness, the young forward is likely to start on the bench after missing the last three months with a metatarsal injury.
Controversial striker Samuel Eto'o has been left out of the squad again, as has defensive utility man Edmilson.