Barcelona star Yaya Toure believes Wednesday's Champions League final against Manchester United will decide who is the best team in the world.Barca have already won the Spanish double this season and United have just clinched an 11th Premier League title."Everyone is excited about this game because we are the two best teams in the world," Toure, 26, told BBC Sport."It will be a great game in Rome as there will be 22 great players taking part - and it could go either way."Barcelona have enjoyed a stellar season, scoring 156 goals in all competitions and producing some outstanding football in the process.But Toure, whose brother Kolo plays for Arsenal, is under no illusions as to the size of the task that faces them at the Stadio Olimpico."It will be very difficult because Manchester United are a fantastic team, you have to be to win what they have won," added Toure."They are physically very strong, they have a truly great footballer in Cristiano Ronaldo and they won the Champions League last year, so we know it will be very difficult."It will be a great game and it's important that we play at 100% because anything less and you cannot beat this team."But we have plenty of confidence ourselves because we won the double and we believe we can win the trophy."Ivory Coast international Toure, who has spent his career as a central midfielder, may be asked to play at centre-back by Barca because of injury and suspension problems.He played there against Chelsea in the semi-final, second leg at Stamford Bridge and is happy to play anywhere for the benefit of the team."I am lucky because I get to play in midfield all the time, I like it there and feel I'm playing some very good football," stated Toure."But if Barcelona need me to play at the back, I will do it - I will try my best anywhere for the team."I can play in the defence too and the only thing that matters on a night like Wednesday is what is best for Barcelona, not me."Source: BBC