Even though Barcelona wins their outstanding match, they will have 63 points, which means they will be leading Real Madrid with 3 points in the La Liga table, which is not enough for Barcelona to win the La Liga league title because Real Madrid can equal the point difference if Barcelona loses one match and Real Madrid wins their match. If Barcelona want to be the favorite to win this season's La Liga title, they need to be consistent in winning their matches to get the opportunity to lead Real Madrid with at least 6 points to have a good advantage over Real Madrid in winning the La Liga title this season.
When the season comes to its ending weeks, with very last matches, 3 points in difference are big enough to secure a title. The season in reality still has many remaining matches and 3 points are not too much and not safe for Barcelona to make sure they will lift the league trophy. At least if they can make diference to not only goal difference but point difference with 3 points, it's better.
Barcelona still have best advantage in the title race and they are controlling the race, but Real Madrid won't give up and there are potentiality of rank changes in La Liga. Atletico Madrid have most disadvantage but they won't give up and will fight best first and wait for results of Real Madrid and Barcelona in coming weeks.
If it happens that Barcelona wins their outstanding match and leads Real Madrid with a 3-point difference till the last match day of La Liga this season, 3 points are a big points difference, which can guarantee Barcelona the La Liga title if they beat their opponent on the last match day of La Liga. Yes, Barcelona has the best advantage over Real Madrid and Atletico Madrid to win the La Liga title because if Barcelona doesn't lose any of their remaining matches this season, they will lift the La Liga title. In my opinion, this season the La Liga title race is just between Barcelona and Real Madrid. I don't see Atletico Madrid as a threat to Barcelona and Real Madrid for the La Liga title this season.