In La Liga, each team has played about 17/18 matches. In my opinion, the title fight will only be between Sevilla and Real Madrid. Real Madrid collected 43 in 18 matches and Sevilla collected 37 in 17 matches. Betis and Vallecano, the third and fourth teams in the table, have collected 33 and 30 points respectively. Atletico Madrid and Barcelona have yet to collect 30 points. Sevilla are playing well, but are they strong enough to win the title? I don't think so. Their next match is against Barcelona, they will be able to win against Barcelona. But I'm not sure if they will be able to maintain a good performance by the end of the season.
but now even if madrid lose the match in week 19 they will still be champions in the second half of the season.
on the other hand maybe sevilla should also be able to make a win in the last match before their break in order to keep hope to continue to stick closely to madrid in first position.
but the opponent they have to face is barcelona.
for now sevilla's performance is much better but maybe barcelona will surprise you