Whether Barcelona is playing carefully or not when Barcelona played against Villarreal yesterday in La Liga, I personally still believe Xavi will keep trying to beat Manchester United. It doesn't matter whether Barcelona won the European League title later or not, because the most important thing for them is to maintain their good trend to be able to beat a strong team from the English Premiere League because of course this is a match with high prestige.
Apart from that, it is indeed an unfortunate result regarding Manchester United which seems to be experiencing a slight decline in performance. Therefore, Barcelona's chances at this moment are getting better to be able to win the match.
I know it won't be easy for Barcelona to complete with Manchester United but the way xavi has built Barcelona they can be able to challenge any club in Premier league with good performance even if the doesnt end with a win for Barcelona. Their is hope Barcelona performance towards Manchester United won't be bad.