Paris Saint-Germain inflicted the first defeat of Luis Enrique's Barcelona reign with a 3-2 win at the Parc des Princes on Tuesday.
The Ligue 1 champions were without talismanic striker Zlatan Ibrahimovic as well as Thiago Silva and Ezequiel Lavezzi, but held off late Barca pressure to end the visitors' unbeaten start to the campaign and dampen an historic occasion for midfielder Xavi.
Coming off the bench to make a record 143rd appearance in the UEFA Champions League proper, the former Spain international was on the losing side after defender David Luiz - a target for the Spanish giants in the close-season - showed his quality in the final third with a smart turn and finish to give PSG what proved to be a short-lived lead after 10 minutes.
Lionel Messi was the man to restore parity less than two minutes later in the Group F clash as he swept home Barca's 500th Champions League goal, although PSG were ahead again shortly before the half-hour mark.
After Marc-Andre ter Stegen failed to collect a deep corner, Marco Verratti headed home his first PSG goal, with Blaise Matuidi making it 3-1 early in the second half.
While Neymar's smart finish from inside the area gave Barca hope, PSG had not lost at home in Europe since November 2006 - a record they maintained with some stoic late defending.
When Sergio Busquets lost possession cheaply early on, former Barca man Thiago Motta blazed PSG's first attempt over the crossbar as the hosts began brightly.
That lively opening was rewarded when Luiz brought down Lucas Moura's free-kick and rolled the ball past Ter Stegen as Barca conceded the first competitive goal of Luis Enrique's tenure.
PSG's joy was brief, however, as Messi capped off a slick exchange with Andres Iniesta to level and end his run of three Champions League games without a goal - the Argentina star's longest goalless sequence since May 2009.
Edinson Cavani was next to go close - the Uruguayan firing over from distance after bamboozling Jeremy Mathieu - before Neymar could only prod Messi's expertly dinked throughball over the crossbar.
Verratti then took advantage of some questionable goalkeeping from Ter Stegen, heading in Motta's looping corner after 26 minutes.
While Messi came close with a curled free-kick, PSG maintained their lead until the break and Cavani threatened soon after the interval as he cut inside Jeremy Mathieu and into a shooting position, only to slip at the vital moment.
PSG's pressure eventually brought a third goal after 54 minutes when Matuidi swept home Gregory van der Wiel's delivery from the right, although, as in the first half, Barca hit back soon after.
Neymar controlled Dani Alves' delivery on his chest and delicately placed the ball past Salvatore Sirigu before Xavi came on to make Champions League history.
Iniesta - making his 100th appearance in the competition - fired over late on and Marquinhos then blocked Jordi Alba's goalbound effort.
Substitute Munir El Haddadi struck the post with a fierce drive, but Barca’s search for a point proved in vain as the home side picked up their first win in Europe this term.