#3 He is now an injury prone player

Vidal's rough tackling, tenacious and no-holds-barred style of play means that he never shies away from getting into a tackle, and this has had a resultant effect on his body.
The 31-year-old has become an increasingly injury-prone player and missed a total of 123 days (over four months) of action last season for Bayern.
Barcelona is a club of the highest level, possessing world class players and an illustrious history which suggests that they play to win every tournament they participate in.
The average season for Barcelona entails at least 55-60 matches of the highest quality, and the club needs all its players to remain as fit as possible for the assault on the club's goals towards the end of the season.
So injuries are a liability that a club like Barcelona can ill-afford to have (even though they are part and parcel of the game), so the conscious decision to go all out for a player who has shown to be injury prone in recent years is one which boggles the imagination.