Juventus will have to target Chelsea's midfield if they are to progress to the Champions League quarter-finals at the Blues's expense.

Everyone has been amazed by just how much Chelsea have improved since Hiddink took over, and their defence, in particular, looks much more solid.

But while they have strong players in midfield where Frank Lampard, for example, is magnificent, this area of the team is not as formidable in reality as it looks on paper.

You could see at Stamford Bridge that, early in the game, the Chelsea midfield was difficult to penetrate. Yet as the game wore on, they became more stretched in that area and started to leave gaps. The Juve players were able to take advantage of this loss of shape, and it is something they must do again if they are to knock out Chelsea.

What will make life difficult for Juve is the return to form of Didier Drogba. He scored in the first leg, and seems a different player from the one who could not get into the team under Luiz Felipe Scolari.

In Italy, we all thought Drogba was being left out because his career was on a downward spiral, or because he was way out of form, but you can see from his recent performances that he has great quality.

He has the physical strength to unsettle the Juve defence, and his goal-scoring record at Champions League level is very good. I rate him far more highly than Nicolas Anelka, who is a goalscorer, but who I don't think would do well in Italian football. Drogba is a much better bet.

If Drogba is Chelsea's key man on the pitch, then Hiddink is just as important to their chances with what he does off it.

The Dutchman is an outstanding coach, someone who will drag the absolute maximum from the group of players he has at his disposal. He beat Italy when he was in charge of South Korea in the 2002 World Cup, and lost narrowly with Australia against them four years later, but both those games showed just how good a coach he is.

He has already made a big impact at Chelsea, but the real fruits of his work will not be seen until the end of the season, when he will have had time to impress his methods on the squad.

With that in mind, I would be very surprised if he left Chelsea to resume control of the Russia team. If he is allowed to go back to Russia, it means that something has gone wrong at Chelsea.

Every manager wants to win things, and Hiddink has a far better chance of doing that with Chelsea than he does with Russia.

But just as this is a big game for Hiddink, it is a very important one for Claudio Ranieri, especially with his past at Chelsea. Juve played well in the first leg, and were slightly unlucky to lose 1-0.

Until this weekend, I was convinced Juve would knock out Chelsea, but I have changed my mind because midfielder Mohamed Sissoko and winger Marco Marchionni are unavailable with foot and thigh injuries respectively.

Either Christian Poulsen or Claudio Marchisio will play in midfield, but neither man is in the same class as Sissoko, while Marchionni has been hugely important on the right-hand side of midfield.

These absences will weaken Juve to such a degree that I now believe Chelsea will get the result they need.