The Blues are sitting at the top of the Premier League table and level on points with second placed Liverpool FC after five games.
Chelsea FC have beaten Huddersfield Town, Newcastle United, Bournemouth, Arsenal and Cardiff City in the Premier League so far.
The west London side will make the short trip to West Ham after Manuel Pellegrini’s side secured their first top flight win of the season last weekend.
West Ham were 3-1 winners against Everton at Goodison Park to finally end their miserable run at the start of the season under Pellegrini.
Chelsea FC were in Europa League action in Greece on Thursday night following a 1-0 victory over PAOK.
Former Arsenal midfielder Merson believes Chelsea FC will edge to a narrow win against West Ham at the London Stadium on Sunday.
“I fancied West Ham last week, I couldn’t see them getting beat at Everton,” Merson told Sky Sports.
“I thought they would be better away from home this season and would struggle at home. But this game looks after itself, Chelsea at home, the fans will be right behind them.
“But I just don’t think they can live with Eden Hazard. West Ham will have their spells in the game but it won’t be enough. Hazard is up there with the best in the world at the moment.”
Chelsea FC have won the Premier League title in two of the past four seasons under Jose Mourinho and Antonio Conte.
The Blues appointed Maurizio Sarri as Conte’s replacement in July following their fifth-placed finish last term.
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