Cech has been caught in no-man's land leading to confusion in Chelsea's defence
By Alan Hansen
BBC Sport football pundit
The dead ball into the box is a huge part of the English game: if you cannot deal with it then you have major problems.
Chelsea are finding this out to their cost. It's a surprising statistic that of the 13 league goals they have conceded this season, nine have come from set-plays.
They are still the most miserly defence in the league, but the way they are conceding might seem strange given that Chelsea have Branislav Ivanovic, John Terry, Ricardo Carvalho and Ashley Cole at the back.
It doesn't really matter how good a defender you are. If you have a player who can ping the ball into the danger area and make life unbelievably difficult for the defenders then they are worth their weight in gold.
If the ball is there to be won and it's straightforward then Terry will still win it, but if you have a little bit of indecision in your mind, either individually or collectively, then you might make the wrong movement or take up a wrong position.
The higher the defence can be when the ball comes in the better
It's quite clear that Petr Cech is having problems with his confidence. He used to be totally in command of his area and he still makes fantastic saves but he is not as decisive since his head injury and that's a big shame.
There has been all sorts of statistics about who scores the most from set-plays and who concedes the most and I think the team that concedes the least is Manchester United and they're one of the smaller teams.
That shows you that defending in this respect is all about organisation, communication and making strong decisions so that everybody knows whether the keeper is going to come and deal with it or stay.
It's certainly had an effect on Chelsea's defenders. If you know the keeper is going to come and meet the ball all the time, that's no problem. It's also fine if the keeper is going to stay in his goal all the time.
But when a keeper comes forward and then goes back or you think he's going to come and then he doesn't - that's when communication goes out the window and leads to indecision and mistakes. In Cech's case he gets caught in no-man's land.
When I was at Liverpool we never practiced set-plays at all.
The fundamentals were all there, we knew what the set-up was, everybody took their positions and then it was up to yourself. We weren't out of this world defensively in the air but we weren't bad either.
And we had a keeper in Bruce Grobbelaar that came out to meet the ball every time.
It was sensational television when he came and missed it but a huge percentage of the time he would get it. For a central defender having the knowledge that he was coming was invaluable, even though I got a few punches in the head!
Of course, in the modern game there is a high value on set-pieces.
If they are good enough then all you need for the ball to go in is a touch off the defender, the attacker or even no touch at all. That's why you will often see right-footers taking kicks from the left and left-footers taking kicks from the right.
Middlesbrough 0-1 Cardiff
We saw one in the game between Middlesbrough and Cardiff last weekend when a great ball in was sent in, no-one touched it and it went straight in.
The problem in these situations for Chelsea, and I've done this a hundred times myself, is that you go to the sanctuary of the goal and get deeper and deeper. That's often born out of insecurity and not wanting anyone to have a free header.
To fix this, it's up to whoever is in charge whether it's the captain, the lead centre-back or the goalkeeper to get the defence out. You have to be vocal, you need to have leaders.
The higher the defence can be when the ball comes in the better.
The other thing you can do is what Wolves did against Bolton the other week where the defence can run out en masse. What that does is get the opposition watching for you coming out, so they don't venture as far as they would normally.
There's all sorts of tricks you can employ but basically the fundamentals are that you've got a keeper and a back four that have got lots of communication, everybody knowing their job and exactly what's going to happen when the ball comes in.
You can never say these situations are undefendable but you have to remember the offside law has changed and that makes it more advantageous for the attackers.
When you used to get the defence out, a player would be offside and he would be penalised, but now there's players that might not be interfering with play so the defenders have to be doubly wary about pushing up.
But at the minute when the ball is coming into the box it doesn't matter whether you are playing against Manchester United or Portsmouth (as Chelsea are on Wednesday), you're still going to be up against it with a good quality delivery.
Every team in the league now, when they get anywhere near the Chelsea goal, will do the same thing.
With that in mind you would have thought that Chelsea have been practising on the training pitch. Otherwise this run of four games without a win could continue.
Alan Hansen was talking to BBC Sport's Alistair Magowan
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