Sarri, having seen his team drop their first points of the season in a goalless draw at West Ham on Sunday, heads to Anfield next for a Carabao Cup third round tie on Wednesday.
Jurgen Klopp’s team will then test their 100 per cent record at Stamford Bridge on Saturday evening.
‘They are a step forward of us at this moment,’ said Sarri when asked about Liverpool. ‘We have to play against a very, very good team who have worked with the same coach for three years.
‘We have started to work together 40 days ago, less 10 days for the international break, so for us it is a bit early. We have to work and then, maybe, in one year we will be at the same level as Liverpool.’
Klopp’s team top the Premier League having won their first six games of the campaign. They beat Southampton 3-0 on Saturday.
‘It will be a really difficult match,’ said Sarri. ‘Maybe spectacular but for us, difficult. I don’t think there is an easy game against Salah, Firmino and Mane.’
The Chelsea boss will make changes in the Carabao Cup tie as he did in the Europa League.
‘Maybe I will have to change 11 players, maybe only five,’ said Sarri.
‘They have one day’s rest more than us and I want to see the picture of the situation when we train tomorrow.’
Antonio Rudiger came off against West Ham with a tight hamstring but hopes to be ready for the weekend as does Pedro who missed the game at the London Stadium through injury.
‘We need to move the ball quicker,’ said Sarri. ‘We need more movement without the ball. We are improving in the defensive phase.
‘In the last two or three matches, we have done very well, but we have to improve in the offensive phase, especially in this kind of match.’