Barcelona ended a difficult year with another disappointing result as they were held 1-1 at home by struggling Eibar on Tuesday.
La Liga: Real Madrid sit behind Atletico on goal difference, but have the better head-to-head record, which is how level teams are split at the end of the season.
Real Madrid secured a 3-1 win against Eibar at the Estadio Alfredo Di Stefano on Sunday.
After scoring Real Madrid's third goal in the 37th minute, Marcelo dropped onto his left knee and raised his clinched right fist into the air.
Lionel Messi had gone four games without a goal in La Liga, his longest drought since 2014.
Trouble returned to Real Madrid after they endured their first La Liga defeat of the season at newly-promoted Real Mallorca.
This was Barcelona's fifth consecutive victory in all competitions, a sequence which is swiftly erasing memories of their stumbling start to the season.
Atletico Madrid have won all of their opening three La Liga games and move five points clear of Barcelona.
Gareth Bale departed again to whistles with 14 minutes left, a conciliatory hand slap from Zinedine Zidane offering little consolation as he trudged off.
Eibar shoot up to seventh, a reward for their first ever victory over Real Madrid at the 11th attempt.