Barcelona's 2-2 draw at Celta Vigo means Ernesto Valverde's side have set a new record for the longest unbeaten run from the start of a La Liga season.
The runaway leaders have now played 33 matches, won 25 and drawn eight in their 2017-18 top-flight campaign.
Saturday's 2-1 win over Valencia made it 39 games unbeaten overall in La Liga, dating back to last season, to surpass Real Sociedad's previous best mark of 38.
The bulk of the work in Sociedad's run came in the first 32 matches of 1979-80, but Barca overcame Sergi Roberto's red card and some late scares at Balaidos to surpass another all-time record set by the Basque club.
33 - Barcelona haven't lost in the first 33 league games (W25 D8), the best starting without defeat in La Liga ever (surpassing to Real Sociedad in 79/80, 32). Record April 17, 2018
Ousmane Dembele's first La Liga goal for Barcelona gave them a 36th-minute lead on Tuesday but Jonny Otto levelled in first-half stoppage time.
Paco Alcacer restored the visitors' advantage shortly after Lionel Messi's introduction from the bench with an hour played, but Iago Aspas – the Spain forward who was fouled by Roberto to prompt the substitute's premature departure – levelled with eight minutes remaining.
