Imagine having a player of this caliber and benching him in the biggest match of the year, on Anfield, while needing midfielders who keep the ball well.
Serious candidate for the managerial failure of the decade. Could've very well been the difference between 5 Champions Leagues, and 6.
It's true he had some muscle problems which led him to have some loss of form but if you ask me, Valverde wanted to reward Vidal for his form and wasn't willing to budge on benching Busi/Rakitic so Arthur had to be sacrificed in his mind.
Despite the warnings vs Liverpool at home, Valverde still thought the Vidal-Busi-Rakitic was the way to go even though everyone and their nan could see the problems with that Midfield. And we ended up paying the price for it.
Did Arthur's muscle problems play a part? sure but the biggest problem was Valverde's persisting with the status quo and not willing to bench the likes of Rakitic and Busi even if they were in poor form. There was no reason for the likes of Arthur and Vidal to be pitted against each other while the other two get a free fucking pass.
the only positive thing I could say is at least Valverde is moving away from the likes of Rakitic and using him and Vidal as sub-options this season.