The current holders wasted no time in kick-starting the new campaign with Alexis Sanchez slotting home on the third minute after some unselfish play by Cesc Fabregas. The Spanish midfielder, who put in a Man of the Match display, was then involved as Lionel Messi doubled the lead with a neat finish.
Brazilian full-back Dani Alves then made it three after Fabregas' effort fell into his path for a simple tap-in before Messi played in Pedro to fire into the bottom corner. With the interval approaching, Messi made it five from the penalty spot after Adriano was brought down inside of the area and Xavi added a sixth moments later with Fabregas involved yet again.
The second-half only saw Barcelona add one more goal - Pedro applying a simple finish after a mix-up in the Levante defence - but it did see summer signing Neymar make his long-awaited league debut, much to the delight of the home crowd. But he was unable to add to the score line as Barcelona started their season exactly where they finished last time around.
Another manager taking charge of his first La Liga game was Carlo Ancelotti at Real Madrid. The Italian endured a majorly frustrating evening but he watched his side leave it late to secure a 2-1 win at home to Real Betis, thanks to a header from summer signing Isco.
Against the odds it was the visitors who took the lead. 31-year old striker Jorge Molina converted from close-range following an industrious run into the area by Cedric, who left Sergio Ramos chasing shadows. Having already had a goal disallowed in the opening minutes, Real were denied by the offside flag once again as Damien Perquis put the ball through his own net.
Betis threatened to double their lead with Cedric causing all sorts of problems in attack, but Karim Benzema's cool finish levelled the tie midway through the first-half as the hosts began to dominate proceedings at the Bernabeu. Cristiano Ronaldo had a number of opportunities to fire his side in front, but it was the debutant, Isco, who headed home a Marcelo cross minutes from time to seal the three points.
Elsewhere, in a clash between two sides who narrowly avoided relegation last season, Granada got their season off to a flying start with a win away to Osasuna.
After an evenly-matched opening, the visitors eventually found themselves in front late in the first-half through a Youssef El-Arabi strike. Former Portsmouth midfielder Hassan Yebda then doubled their advantage in stoppage time to take a 2-0 lead into the break.
Osasuna pressed to change the course of the game and it was their influential captain, Francisco Punal, who was able to claw a goal back just before the hour mark. His effort ensured a nervy finish for Granada, but Lucas Alcaraz' men held on to get their campaign off to a winning start.
In the late kick-off, there was disappointment for Sevilla as they were beaten 3-1 at home by Atletico Madrid with Diego Costa grabbing a brace.
Costa, who had played a supporting role to Radamel Falcao last season, took centre-stage with the opening goal of the game 10 minutes before half-time only for Diego Perotti to hit back with an instant equaliser.
But Costa found the winner with a little over 10 minutes remaining in the second-half and Cristian Rodriguez capped it off with a third in injury-time.