The Blues have made a brilliant start to the new season under Sarri following his appointment as the club’s new manager back in July after the sacking of Antonio Conte.
Chelsea FC have won all five of their opening Premier League games to leave them leading the way at the top of the table and level on points with Liverpool FC.
Eden Hazard continued his fine form by hitting a hat-trick in the 4-1 win over Cardiff City on Saturday as the Blues maintained their 100 per cent start in the Premier League.
However, despite their fine start to the new campaign under their new manager, Sarri feels that the Blues still have some significant work to do if they want to challenge the likes of Manchester City and Liverpool FC this season.
Sarri is quoted as saying by Metro: “In my opinion two teams, Liverpool and Manchester City, are better than us.
“We have to improve step by step, and my target is to become the best team in England in one year to 18 months.”
Meanwhile, Chelsea FC are currently preparing for their Europa League group-stage opener on Thursday night against PAOK.
The Blues ended up in fifth place in the Premier League table last season and they also won the FA Cup under Conte last term.
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