After Martin Montoya replaced injured Brazil full-back Daniel Alves in the 14th minute in Valencia, all 11 team members on the pitch were products of Barca's famed La Masia youth academy.
Pearls of the current crop include Argentine World Player of the Year Lionel Messi, Spain playmaker Andres Iniesta and midfielder Cesc Fabregas, who left for a stint at Arsenal before returning to his boyhood club.
Iniesta turned in a sparkling performance, twice setting up Messi, creating another goal for Fabregas and scoring a brilliant effort of his own as the league leaders racked up 37 points from 13 matches this season.
Their tally equalled the record for the best start to a campaign set by Real Madrid in the 1991/92 season.
"It's a fact that should make us proud," Barca coach Tito Vilanova, himself a product of La Masia, said at a news conference when asked about the 11 academy players in the side on Sunday.
"Because what's more seven or eight of them are from Catalonia," he added.
By contrast, only two of the regular starters in the current Real team are from the club's academy, goalkeeper and captain Iker Casillas and full-back Alvaro Arbeloa.
They are coached by Portuguese Jose Mourinho, a former Barca assistant who has been criticised for not giving more playing time to graduates from Real's youth school.
"It's extraordinary, and all the more so for those of us who were trained at the Masia," midfielder Xavi, widely regarded as the finest playmaker of his generation, told reporters.
"It's more proof of the good work that has been done for many years," he added.
"[Former Barca coach Louis] van Gaal said once that his dream was to see 11 academy players together on the pitch and today it became reality."
Defender Gerard Pique, a contemporary of Fabregas and Messi who returned to Barca after a spell at Manchester United, added: "It's a source of pride for all Barca fans that 11 home players were together on the pitch because it shows the academy is in good shape and we are working well."
