Nevertheless, Barcelona's performance can be said to have very positive results. I'm optimistic, Barcelona can beat Rayo easily.
Compared to Rayo Vallecano, see the list of players who strengthen both clubs, Barcelona is more superior based on experience. Considering this is Barcelona's opening match, they need points and Xavi will play a mainstay formation including Lewandowski et al.
Based on the odds, 80% of the win go to Barcelona. Apart from that barca should not underestimate Rayo Vallecano, because it could be an opportunity for Rayo to be more confident. In this match, Barcelona's consistency will be very influential in determining the outcome of next week's match.