The lack of defensive protection Reading's midfield offers its defence has been a problem all season. In fact we highlighted it as an area of concern before the season even started.
By now it is clear that defending is not a priority for Jaap Stam. How we line up defensively has to work around the main tactical priority which is to control possession.
Unfortunately this has led to some heavy defeats for Reading this season, including at Craven Cottage in early December. The Royals went into that game without possibly their best defender Liam Moore and lined up with a four man defence.
That afternoon will be on everyone's minds on Saturday when Reading and Fulham commence battle for the fourth time in half a year. Fulham ran riot and there were some familiar defensive frailties from Stam's team.
The first goal may have been a freak own goal, but two of the goals looked remarkably similar to those seen in other heavy away defeats this season.
Fulham's second came when Reading failed to deal with a long ball allowing Chris Martin to control and shoot from the edge of the box.
Whilst it is more than a little worrying how regularly individual errors appear in Reading's away day miseries, it also noticeable how often the midfield go missing. The picture below shows Martin about to shoot and there is no Reading midfielder in the picture.
Reading's midfield does appear in the below picture for Fulham's fourth goal, but they have both been guilty of switching off. Another inability to deal with a loose ball led to Sone Aluko picking up the ball just off the picture next to Chris Gunter on the left edge.
George Evans starts that incident high up the pitch, but by the time the ball is played to Stefan Johansen he isn't in too bad a place. Unfortunately Joey van den Berg has switched off.
He is far too over the pitch considering that just a second before the ball was out wide. He should be much closer to Evans, but Reading's two midfielders are too far apart allowing Johansen plenty of time to control and shoot.
Part of the problem is that most of Reading's midfielders and attackers are not only given little defensive responsibility, they are also encouraged to play high up the pitch. It is rare for any of the front three to drop deep when Reading build from the back. That means they can have little influence in defence.
When playing four at the back, the two more attacking central midfielders also rarely drop deep. Below is an example of the movements and positions Reading take up when controlling possession.
The centre back split with the full backs pushing on and the deepest central midfielder dropping deep. That leaves the space inside the yellow box without a Reading player.
This can end up looking like three at the back with wing backs. It is very similar but there are a few differences.
For one the midfielder dropping deep is running backwards so isn't facing the opposition.
Stam likes his team to form triangles so that his players have more than one option when they have the ball. As a result the deep midfielder has a license to roam so he can support the centre backs and full backs. That of course means he has to make up a huge amount of territory which can see him out of position when the opposition counter attack.
The difference with a three man defence is shown below. Again the centre backs will split but this time a third centre back is between them rather than a midfielder.
I have shown the movement for when the ball is on the left side. The left central midfielder will drop deep to support the defence which allows the left attacker to move into the vacant space. That allows the wingback to push forward.
Crucially the third centre back is a constant central presence and can push forward to defend the yellow box.
An example of that is show in a Fulham counter attack in the return game at the Madejski Stadium. Liam Moore excellently steps into the space between the defence and midfield to close down Lucas Piazon and makes a superb tackle. He can do that because Paul McShane and van den Berg are covering him.
You can see another example of this below. Moore has tracked the run of Johansen knowing that van den Berg is marking Martin and Tiago Illori, the left wingback, is covering out wide.
None of Reading's three central midfielders, circled in red, are close to the area Moore is marking.
There is a downside to Moore stepping up though. To do that he needs his fellow centre back to be on top of their game and it gives them little margin for error.
Reading seem to be safe in the above picture but Tom Cairney plays a through ball for Lucas Piazon to run onto. As you can see below, van den Berg has switched off for a second and is suddenly out of position. With Moore not able to cover him he makes a desperate attempt to get back and concedes a penalty.
Fulham tend to play four at the back with two very attacking full backs. Another advantage of playing three at the back is that it would allow Reading's wingbacks to push up and mark Fulham's fullbacks.
Of course the alternative is that Stam might decide that starting with a four man defence means his wingers can play wider forcing Fulham's fullbacks to stay deep. Such is Fulham's attacking intent and Reading's slow build up in possession such a tactic may not be that effective. Fulham's fullback will likely attack regardless of what Reading do and they will also know that Reading rarely launch quick counter attacks that could leave them out of position.
With that in mind I would expect Stam to opt for a three man defence and that was what he played against Burton. One thing that might influence his decision is the fitness of Paul McShane. I would be surprised to see Reading start with a back three that does not include their club captain.
Whatever Stam chooses I just hope he is not as cavalier, at least for the first leg, as he has been sometimes this season. Fulham have shown that they will take full advantage of space given to them. Stam may decide to make covering important areas more of a priority than usual.