Barcelona are by far the best in La Liga in all aspects. And since Barcelona managed to defeat Real Madrid in El Clasico, Barcelona are one of the best title contenders ever. Barcelona will never want to miss out on the La Liga title despite performing so well.
the league is not obtained by just 1 or two matches. Barca performed consistently very well throughout the season. they lost their focus for a while, but Xavi noticed and they fixed it quickly.
Madrid lost the momentum to catch up, and now Barca will focus on La Liga, and Madrid will focus on the Champions League. Xavi has made an extraordinary achievement this season.