So far, I agree with you that the La Liga title race will most likely only be between Barcelona and Real Madrid. But the summer transfer window is still under way before it closes on September 1, which means Atletico Madrid still have time to bring in some of the players they are looking to strengthen their squad and participate in the La Liga title race.
Do not think that because Barcelona had 1-2 good games at the end of the season and preseason they will win the league. Truth be told, Barcelona sort of have a fighting chance but their new signings of Lewandoski, Kessie, and Raphinha, but it will not be enough for them to clinch the title. Maybe next season. If you compare Real Madrid starting 11 to Barcelona you will easily tell which is stronger in terms of quality, strength and consistency. Besides, they still have a lot of work to do in their left-back. Having said that, one of the things that worries me though is for Benzema not to get injured.
It is not yet a conclusion that Barcelona are going to win the Lalliga tittle this season because they are still building their team,but even at that,they've had a strong squad that can win the Lalliga tittle this season.Tried Last season, and would have won the tittle if not that Madrid were already ahead of them with so many points,so this season,they have added some quality players that can help them fight for the tittle.So I feel and think that Barcelona will win the Lalliga tittle this season.