Maurizio Sarri took Napoli to a second-place finish behind Juventus in Serie A last season
Chelsea manager Maurizio Sarri says his side are "a step behind" Premier League leaders Liverpool, who they face twice in the next week.
Chelsea go to Anfield in the Carabao Cup on Wednesday, before a league meeting at Stamford Bridge on Saturday.
"They have worked with the same coach for four years," said Sarri after the Blues dropped their first points of the season in Sunday's 0-0 draw at West Ham.
"I think Liverpool are ahead of us."
Manager Jurgen Klopp took charge of the Reds in October 2015, succeeding the sacked Brendan Rodgers with the team 10th in the league.
The German guided them to an eighth-place finish that season, as well as the League Cup and Europa League finals, before making the top four in his next two campaigns.
Liverpool reached last season's Champions League final - losing 3-1 to Real Madrid in Kiev - and the Reds are two points clear at the top of the Premier League this term after winning all six matches.
Jurgen Klopp moved to Liverpool after ending a seven-year spell with Borussia Dortmund in May 2015
Sarri is in his maiden campaign at Stamford Bridge having left Napoli to join the club in July.
His preparations for the new season were hampered by players' participation at the World Cup.
He has made three signings to add to the squad inherited from fellow Italian Antonio Conte, with midfielder Jorginho and goalkeeper Kepa Arrizabalaga arriving from Napoli and Athletic Bilbao respectively, and free agent Rob Green joining as goalkeeping back-up.
However, the Blues have started the season well, winning their first five Premier League games and their opening Europa League group match, before Sunday's draw with the Hammers at London Stadium.
"We have started to work all together 35, 40 days ago. So for us I think it's a bit early," Sarri added.
"We have to work. We need to improve and then maybe in one year we will be at the same level as Liverpool."
Source: bbc.com