Chelsea v Barcelona: 5 key player battles that can decide the outcome

#1 Lionel Messi vs Cesar Azpilicueta

Azpilicueta battling it out with a young Messi during his days with Osasuna

Not many people know of this but the duo has the history of going up against each other in La Liga back in 2009 during Cesar Azpilicueta's tenure with Osasuna in Spain. Since then, the players have hardly looked back in terms of progressing through different levels, bettering themselves in the process.

Messi has already established himself as one of the greatest ever footballers to have graced the pitch while Azpilicueta's meteoric rise with Marseille provoked Chelsea to rope in the Spaniard in 2012 and what seemed like a gamble five seasons ago, seems like one of the bargains of the decade already.

Both players have arguably been their club's most consistent performers over the last year or so and the fact that they will be playing with a lot of expectations weighed upon them could only mean that this could shape up to becoming a crucial player battle that can decide the outcome of the match.