The last time a club was this close to an unbeaten season in La Liga, they came unstuck at Sevilla.
Barcelona, with concerns over the fitness of Lionel Messi, travel to the Ramon Sanchez Pizjuan Stadium on Saturday, looking to extend their own undefeated run this term to 30 league games.
It was Real Sociedad who had gone 32 without loss in the 1979-80 season, when they were only two more away from finishing the then 34-game season as invincibles.
But, in the penultimate match, Sevilla snatched a 2-1 win thanks to Ricardo Bertoni´s double, his second an 83rd-minute winner. Sevilla would finish eighth that year, Sociedad second, one point behind Real Madrid.
Barca will almost certainly not surrender the league title if history repeats itself this weekend, their 11-point lead over Atletico Madrid surely too wide a gap to close, but they would give up the chance of being the first side to end a 20-team La Liga season unbeaten.
They are now three games away from matching Sociedad´s best ever single-season streak and two from equalling that same Sociedad team's longest run without loss overall, which amounted to 38 games when including the previous season too.
After Sevilla, Barcelona play Leganes and Valencia at home, Celta Vigo and Deportivo La Coruna away before hosting Real Madrid on May 6. They then finish at home to Villarreal, away to Levante and at home to Sociedad.
This Sevilla, although sixth and set to miss out on Champions League qualification, arguably represent Barcelona's biggest obstacle in those final nine fixtures.
Valencia, who are fourth, and Real, who would certainly revel in scuppering the bid, will offer stern tests but both at least come at the Camp Nou. Barcelona have not lost a league game on their own patch in 19 months.
Coach Ernesto Valverde has never attached much significance to the unbeaten streak, preferring to focus his players´gaze on the title, but as that prize becomes increasingly secure, he might see it as a welcome bonus.
"We're delighted with how things are going and that record says we must be doing something right," Valverde said in February.
- Bettering Guardiola -
For his own legacy, it would give him something over Pep Guardiola, who oversaw only one league loss in 2009-10 and then 31 games undefeated in 2010-11, but never ended a season with a zero in the losses column.
Fatigue will certainly be a factor, and priorities too. Barcelona and Sevilla both have an opening leg of the Champions League quarter-finals to negotiate next week and, with their fates largely settled in the league, each may choose to rotate.
Sevilla are at home to Bayern Munich on Tuesday and Barca host Roma on Wednesday.
The Catalans face Valencia three days before the return fixture and, if they progress, Real the weekend after the second leg of the semi-finals. Rotation is inevitable.
For now, Lionel Messi is the key concern after he sat out both of Argentina's friendlies against Italy and Spain over the international break due to a hamstring complaint.
Goalkeeper Marc-Andre ter Stegen, meanwhile, is nursing a knee problem picked up on duty with Germany and Sergio Busquets is unlikely to be risked this weekend as he nears recovery from a toe injury.
Real have been less damaged by the international fixtures but Zinedine Zidane is also expected to have one eye on Europe when he picks his team to play Las Palmas on Saturday.
Flying to Gran Canaria ahead of the trip to Turin for Juventus on Tuesday is not the best of preparations and it is likely those that turn out this weekend may then be left out in Italy.
Gareth Bale, snubbed for both of the last 16 legs against Paris Saint-Germain, will be hoping his four goals in two matches for Wales last week has not gone unnoticed. Isco too, after he followed his hat-trick for Spain against Argentina by admitting he does not feel the same confidence at Real as he does with the national team.
Elsewhere, Europa League hopefuls Girona are at home to struggling Levante before second-placed Atletico Madrid entertain Deportivo La Coruna and Valencia visit Leganes on Sunday.
Madrid, Spain | AFP