Lionel Messi and Thiago Alcantara led Barcelona to a dominating 5-0 win over Villarreal on Monday to open the defending champion's campaign for a fourth straight Spanish league title.

Despite a makeshift defense and coming off a European Super Cup victory just three days before, Barcelona responded to Real Madrid's 6-0 rout of Zaragoza over the weekend with another display of its own beautiful game.

Thiago struck first for the European champions, and Cesc Fabregas doubled the score from an assist from Messi before halftime.

The 20-year-old Thiago then found new signing Alexis Sanchez to extend Barcelona's advantage, and Messi capped the victory at Camp Nou with a pair of goals from passes from Iniesta and Thiago.

Barcelona has now gone undefeated in all competitions at Camp Nou since last season's home opener.

With starters Carles Puyol, Gerard Pique, Adriano and Maxwell all out with injury, and Dani Alves serving a suspension from last season, Guardiola experimented with a three-man defensive line with Eric Abidal alongside reconverted midfielders Javier Mascherano and Sergio Busquets.

Even with the new system and Spanish internationals Xavi Hernandez and David Villa on the bench, Guardiola's team continued to mesmerize with its possession-based attack.

Villarreal tried to stay true to its game plan by playing Barcelona up the pitch, but the hosts had little trouble breaking the pressure down with short passing combinations.

Thiago broke through in the 25th when Spain midfielder received the ball outside the area and coolly slid forward before picking his spot and slotting the ball through a pack of defenders into the right side of the net.

Italy striker Giuseppe Rossi had Villarreal's only chance in the first half when he got behind the defense moments later, only to send his volley into the side netting.

Reminiscent of Barcelona's second goal in the European Super Cup on Friday, Messi and Fabregas continued to show the connection they developed as teenage teammates as the Argentine star left Fabregas with only goalkeeper Diego Lopez to round and tap home.

While Barcelona was content to strangle Villarreal's passing game with its control of the ball in the first half, it quickly put the game out of question right out of the break.

Sanchez netted his first goal in an official game for his new team in the 47th when he latched on to a lobbed pass from Thiago and fired past Lopez into the far side of net.

Four minutes later Andres Iniesta played Messi through the center of the defense for him to beat Lopez one-on-one.

The demoralized Villarreal defense collapsed completely when another one-touch combination left Thiago alone on the flank to cross for Messi to deflect in.

Messi is making a strong bid to win his third straight Ballon D'Or after his sixth goal in four games.

Over the weekend, Cristiano Ronaldo scored a hat trick to lead Real Madrid to its thrashing of Zaragoza.

Roberto Soldado netted his own hat trick - with two goals coming in the final minutes- to rally Valencia to a 4-3 comeback win over Racing Santander.

Also, it was: Sporting Gijon 1, Real Sociedad 2; Granada 0, Real Betis 1; Atletico Madrid 0, Osasuna 0; Athletic Bilbao 1, Rayo Vallecano 1; Getafe 1, Levante 1; Mallorca 1, Espanyol 0; Zaragoza 0, Real Madrid 6; and Sevilla 2, Malaga 1