While Barcelona rolled to victory, Real Madrid needed a late header by new midfielder Francisco "Isco" Alarcon to edge out Real Betis 2-1 at home in the first game with Carlo Ancelotti in charge after three season under Jose Mourinho. (Agencies)
Madrid's lackluster showing will add more pressure on president Florentino Perez to pay the hefty price Tottenham desires for forward Gareth Bale to reinforce its attack.
Also, Atletico Madrid forward Diego Costa did his best to erase memories of Radamel Falcao by scoring twice, including a well-taken go-ahead goal off the break in the 79th minute, to lead a 3-1 win at Sevilla. Granada, meanwhile, won 2-1 at Osasuna.
With signature signing Neymar watching from the bench, Messi almost single-handedly dismantled the overmatched Levante.
After Alexis Sanchez opened the scoring, Messi claimed Barcelona's second goal, stole possession to create the third, and passed for Pedro Rodriguez to score the fourth.
Messi scored his second goal from the penalty spot before Xavi Hernandez made it 6-0 against the demoralized visitors to equal a club record of goals in a first half.
Neymar, who has been recovering from anemia since his a 57 million move from Santos in the offseason, went on in the second half in time to see Pedro strike again and polish off the lopsided victory.
The applause Neymar received while warming up grew to a standing ovation when he went on for Alexis in the 64th for his first official minutes in Barcelona's burgundy and blue.
Those eager to see Neymar and Messi together were disappointed, however. The two were only on together for seven minutes before Martino sent Andres Iniesta on for Messi.
The 21-year-old Neymar was active on the left flank but couldn't find his new teammates with crosses. Goalkeeper Keylor Navas saved his best chance before he was booked for tripping.
Martino said that he had agreed with Messi to take him out once the game was resolved, keeping in mind the long season ahead and that the player is coming off a hamstring injury.
While Barcelona rolled to victory, Real Madrid needed a late header by new midfielder Francisco "Isco" Alarcon to edge out Real Betis 2-1 at home in the first game with Carlo Ancelotti in charge after three season under Jose Mourinho.