If the outcome of a match is random then this equation can easily be changed. Barcelona knows that the difference of 3 points is not a big difference at all, that's why they don't want to make mistakes in any match. If in any match Barcelona makes a mistake and Real Madrid does well, then Barcelona will fall behind and Real Madrid will once again go to the top of the points table. The competition in this league is going to be tough and whichever team Barcelona Real Madrid or Atlético Madrid wins the title will ultimately compete hard and then win the title.
A small point gap will always show a fiercer competition until the end of the season because all three teams are still quite aware of their own chances in this season although it must also be seen from the possibilities that can happen to them in the next few matches. For now, all three teams still have the potential to win the remaining matches even though Atletico Madrid is seven points behind Barcelona, but Atletico Madrid should not be written off as a candidate to compete for the title this season because there is still time for them to reduce the points gap.