Carlo Ancelotti insists Chelsea possess the best defence in the world and that will be key to winning the Premier League title.

Chelsea are without the injured Frank Lampard, Didier Drogba, Deco and Michael Ballack for Saturday's match against Wolves.

But Ashley Cole is set to return from injury and John Terry will be back after missing England's friendly against Brazil.

Ancelotti also intends to pack his substitutes' bench with young players such as Fabio Borini, Nemanja Matic and Gael Kakuta.

The manager, however, believes Chelsea's backline is better than his celebrated defence at AC Milan which contained Paolo Maldini and Alessandro Nesta.

Ancelotti said: "If you want to win a cup or a championship it is important not to concede a goal. We have fantastic defenders in Terry, Carvalho and Alex. Chelsea have the best central defenders in the world at the moment.

"Defence is the key. If you don't concede a goal the worst it can be is 0-0. We have four central defenders and nobody has this quality."

Ashley Cole will play with a special shin guard to protect the depressed fracture of the tibia he suffered in the Champions League win over Atletico Madrid last month and which required a pain-killing injection against Manchester United before the international break.

Drogba, however, is unlikely to play in the Champions League against Porto next Wednesday as he continues to recover from the rib injury he suffered against United in a clash with defender Jonny Evans.

Ballack will also be missing against Wolves with a knee injury after a traumatic week in which he mourned the suicide of his international team-mate Robert Enke.

Ancelotti said: "It has been a very difficult week for Ballack but he will be ready for Porto. He has a problem with his knee but he can play on Wednesday.

"He is an intelligent player who helps the defensive line. His character and personality is strong. He is a leader."

Ancelotti also revealed that he intended to use young players such as Borini, Matic and Kakuta when he loses his African stars to the African Nations Cup in January.

He said: "The aim is to retain players in good condition. We have to play without the African players in January. We don't want to take players on loan. We can use young players in that period on the bench."

First, however, Ancelotti is determined to preserve Chelsea's five-point lead at the summit of the Premier League, starting with struggling Wolves tomorrow.

He said: "I know against Wolves we will have to pay attention. They have good strikers and they will be hungry."

Ancelotti also shed some light on midfielder Michael Essien's no-show for Ghana in midweek.

He said: "It is simple. He asked the manager of Ghana if he could avoid the game on Wednesday. We gave him a day of rest and it was no problem.

"I didn't speak with the Ghana manager. I spoke only with Essien."