Sevilla are 9 points behind Real Madrid, but have played one game less and are currently leading 1-0. If they are going to win this match (that chance is quite realistic) then the gap is only 6 points. That in itself can still be bridged, especially since Real Madrid have proved vulnerable in several matches lately and it occasionally drops below their level. I really never expected Sevilla as a serious title contender. Do they still have to play against each other? That would be crucial.
Sevilla is close enough to get a big win but I still don't think that make them a big threat for Real. I don't see Real to lose points against weaker teams, although they have though opponents in the fixture. If they pass this timeframe with minimal damage they will be ready to celebrate another championship. Real Madrid lost only two games this whole season, unless they get a draw streak or something I don't think Sevilla can catch them. Sevilla also need to be faultless in case of Real's point losses, which is hard considering they still have to play against Barca and Atletico.
There are 12 matches left in La Liga this season and Sevilla are still 6 points behind it means there is still a chance, 3 of 12 Madrid matches were big matches
The determination can be seen from these 3 important matches, if Madrid manages to win 2 of them then it is certain that Madrid is the champion. On the other hand, if Madrid only win one game the competition will continue.
Don't lift your hopes high up just yet. Madrid were having hard time against Vallecano so it is also possible that they might get suprised out against some underdogs. I would have agreed with you if they have been in best shape but they are not in best shape right now. They have CL match to play and win the match and advance to next stage so they probably wouldn't be 100% fit for the next LaLiga match after then so it would be a great opportunity for their next opponent.
I think to maintain a flawless run is very tough especially when a team is not in best shape.