West Bromwich Albion proved they are a legitimate Premier League force by beating European champions Chelsea 2-1 on Saturday as Manchester City crushed Aston Villa 5-0 to go top of the table for the first time this season.

Peter Odemwingie scored West Brom's winner after 50 minutes at the Hawthorns, sending the home side into fourth place and ruining the return of former Baggies manager Roberto Di Matteo.

It left third-placed Chelsea off the pace after two goals from Sergio Aguero and Carlos Tevez gave defending Premier League champions City a comfortable day at the Etihad Stadium. City have 28 points from 12 matches. Chelsea have 24 points from 12 games with Albion a point further back.

Arsenal kickstarted their season in the early Saturday kick-off by beating north London rivals Tottenham Hotspur 5-2 after Spurs striker Emmanuel Adebayor had been sent off shortly after giving his side the lead.

Southampton increased the pressure on QPR manager Mark Hughes by winning the basement battle 3-1 at Loftus Road, and Reading surprised Everton with a 2-1 win at the Madejski Stadium, their first league win of the season.

Liverpool beat Wigan Athletic 3-0 at Anfield, with two goals from Luis Suarez, and Swansea City enjoyed a 2-1 victory at Newcastle United.

West Brom fans gave Chelsea manager Di Matteo a warm welcome on the Italian's return to the Hawthorns, and then their team showed him how far they had come since he left in 2011.

The home side were ahead after 10 minutes, when Shane Long shrugged off Chelsea defender David Luiz in the area to head home a cross from James Morrison.

Di Matteo had rested Brazilian Oscar and Spaniard Juan Mata but six minutes before the break, another of the club's galaxy of talents, Eden Hazard, emerged. The Belgian began the move for the equaliser by finding Cesar Azpilicueta, who returned the favour by crossing to the far post for Hazard whose header took a deflection before beating Boaz Myhill in the West Brom goal.

But it was another header that gave West Brom the edge, Long this time the provider and Odemwingie nodding the cross through Petr Cech's legs.

Di Matteo brought on Oscar and Mata, and withdrew Fernando Torres, but Daniel Sturridge missed two late chances as West Brom held on. The result was also a personal triumph for Steve Clarke, the West Brom manager and former Chelsea coach and player.

In the north London derby in the early kick-off, former Arsenal striker Adebayor gave Spurs the lead after 10 minutes but seven minutes later the Togolese dived into a tackle on Santi Cazorla and was shown a straight red card. Germany defender Per Mertesacker equalised for Arsenal with a powerful header after 24 minutes, and Arsene Wenger's side scored twice in the last three minutes of the first half -- through Lukas Podolski and Olivier Giroud -- to take control. Spaniard Cazorla made it four from Podolski's cross on the hour, and although Gareth Bale's right-foot shot from the edge of the area gave Spurs some hope, Theo Walcott completed the scoring from close range in injury time.