Barcelona
The Catalans have won everything. Betis (2-0), Alavés (0-2), Espanyol (5-0), Getafe (1-2), Eibar (6-1) and Girona (0-3). Six out of six in La Liga.
Napoli
The Italians have also won six games in the Serie A, against Hellas Verona (1-3), Atalanta (3-1), Bologna (0-3), Benevento (6-0), Lazio (1-4) and SPAL (2-3).
Juventus
Juventus top the league table alongside Napoli thanks to wins over Cagliari (3-0), Genoa (2-4), Chievo Verona (3-0), Sassuolo (1-3), Fiorentina (1-0) and Torino (4-0).
Porto
Seven wins for the Portuguese side. Estoril (4-0), Tondela (0-1), Moreirense (3-0), Braga (0-1), Chaves (3-0), Rio Ave (1-2) and Portimonense (5-2) have suffered the blunt of Porto's unstoppable start.