Lionel Messi scored a hat-trick as Barcelona turned around a 3-1 first-leg deficit to claim the Supercopa with an impressive win over an under-par Sevilla side at the Nou Camp on Saturday.
David Villa came on to make his debut late on and new president Sandro Rosell was in his box seat for the first time in a night of celebrations.
Rosell was to win his first trophy as Barca chief, but the Catalans were also presented with the league trophy they won last season and welcomed back their World Cup winners too.
Five of Barca's eight Spain stars started this match, with Villa, Carles Puyol and Andres Iniesta on the bench. But it was the youngest of them all, Pedro, who set Barca on their way after 14 minutes as Abdoulay Konko scored an own goal.
The Tenerife-born forward beat two Sevilla players on the right wing, advanced into the area and saw his low cross deflected into the net by Konko. It was a soft goal from Sevilla's point of view and a bad time to concede as well.
The Andalusians, with one eye on Tuesday's Champions League qualifier against Braga, began without their two star strikers, Luis Fabiano and Frederic Kanoute.
Alvaro Negredo and Alejandro Alfaro began in their place, but were feeding off scraps up front. The Catalans were dominating almost effortlessly and a second goal appeared only a matter of time.
Bojan Krkic and Maxwell both came close before Messi ran on to Xavi's perfectly-weighted slide-rule pass to slot home after 25 minutes.
A 2-0 win was all that Barca needed to reclaim the Supercopa, but there was still more than an hour to go. And Messi was in the mood.
The 24-year-old latched on to Dani Alves' pass in the area a minute before half-time and beat Andres Palop with a fierce angled shot which gave the keeper no chance.
Messi could have completed his hat-trick five minutes after the break, but dragged his shot side of the target.
Villa came on for his debut short of the hour mark and showed some moments of inspiration, but it was another Barca substitute, Iniesta, who created the fourth goal.
Spain's World Cup hero charged into the area in the last minute after playing a one-two with Villa and unselfishly laid the ball back for Messi, who slotted home to complete his hat-trick and round off a perfect night for the Catalan club.
It was a first title for Rosell, but an eighth for Guardiola in what is the beginning of only his third season in charge.
Captain Puyol, who sat out the whole 90 minutes, came on to lift the trophy after the match on a happy night at the Nou Camp, and a welcome return to form for Messi following his World Cup disappointment with Argentina.