Liverpool manager Jurgen Klopp says that Chelsea have become more dominant in and focused on possession since Thomas Tuchel arrived.
Klopp’s fellow German replaced Frank Lampard in January after a dismal run of Premier League form.
However, the Blues have now re-entered the race for the top four, before Thursday’s crucial clash with Liverpool.
Chelsea sit a point behind fourth-placed West Ham, with the Reds two off the Champions League spots.
Tuchel has yet to lose since taking over at Stamford Bridge, guiding his side to six wins from nine games.
As such, Klopp is wary of the threat their rivals pose ahead of this week’s meeting at Anfield.
The manager said of Chelsea: “Clear philosophy, clear idea, absolutely possession-based, different formations. [Tuchel] really changed a lot, all three left-backs played.
“Up front there’s a lot of options, he’s changed them and tried them all. It’s just Mason Mount, Kovacic and Jorginho as the fixed points, but he changed a lot to get information about the squad.
“I think now they are a step further and we will face them now.”
Asked in Wednesday’s pre-match press conference if his Liverpool stars need to be patient, Klopp added (via the Liverpool Echo): “It’s quite difficult to get more possession than Chelsea, that’s changed since Frank.
“But the full package will be required. We have to defend, we have to work a lot, we won’t face a deep block.
“We have to be patient in moments and lively, creative and show desire to defend. They’re a top team.”
Klopp said that he “expects” Alisson Becker to play after the goalkeeper sat out Sunday’s clash with Sheffield United on compassionate grounds.
Fabinho and Diogo Jota could also play a part after injury.
Klopp hopeful of injury boost
“Ali trained now the full week so we should expect that he’s able to return,” Klopp said.
“Fab has now five or six sessions in his legs. We have to make a decision how we deal with that, but looks good. He is ready for the squad, for sure.
“Diogo had this little stomach problem. He trained yesterday, only a little bit. I got the message this morning that he feels better again, so we will see.
“Before it looked exceptionally well and we have to see how big the steps are he can make to the team again.”
Liverpool beat Chelsea 2-0 at Stamford Bridge in the season’s earlier meeting between the sides in September.