By Lee Dixon
BBC Sport pundit
If there is one area of the England team that has divided opinion in recent years, it is the midfield.
The perennial problem for the England manager used to be who would play down the left.
The main bone of contention then became whether Chelsea's Frank Lampard and Liverpool skipper Steven Gerrard could play together in the middle, but, thanks to Gareth Barry's success as a holding midfielder, that is no longer an issue either.
The Manchester City left-footer is now a regular in the England set-up, enabling the likes of Lampard and Gerrard to play successfully in the same team and do what they do best.
Barry might not have the X factor of his Chelsea or Liverpool rival, but his importance to England is illustrated by the fact he has started nearly every game since he was brought into the side during qualifying for Euro 2008.
But does Barry limit England's attacking options in some games? Or would he be helped in other matches by having another holding midfielder next to him, like Manchester United's Michael Carrick?
In this week's World Cup scouting report, I assess Barry's importance to the England team and ask whether he is the best man for the job.
Barry's reputation and worth was underlined two summers ago when Liverpool wanted him to replace Xabi Alonso. That move to Anfield never happened and Barry ended up staying at Aston Villa for another campaign before joining City at the start of this season.
The 29-year-old has admitted that under former England boss Sven-Goran Eriksson he had despaired of ever making the international breakthrough. But under the Swede's successor, Steve McClaren, he got his chance and almost instantly provided balance and stability to the England midfield.
Barry is definitely in the driving seat as far as the position of holding midfielder is concerned, although things could have been different had Manchester United's Owen Hargreaves been fit.
BARRY AND CARRICK THIS SEASON
29 - League appearances - 28
7 --------- Assists --------- 2
2 ---------- Goals ---------- 2
36 - Total England caps - 21
Hargreaves was arguably England's best player at the last World Cup, but the former Bayern Munich player's career has been blighted by knee injuries, allowing Barry to capitalise. Hargreaves is nearing a return to first-team action at United but it is unlikely he will play in South Africa.
Hargreaves's club-mate Carrick is a certainty for the England squad, however, although I think he will be hard-pressed to make the starting XI.
If you play Barry and Carrick together from the start, you either have to lose one of your key players in Lampard or Gerrard, or sacrifice width by taking off your right winger. That's unlikely to happen, although England manager Fabio Capello could turn to Carrick if he wants his team to shut a game down or maintain possession.
West Ham's Scott Parker and Tottenham's Tom Huddlestone have been suggested as possible contenders, but I think they are way behind Barry and Carrick in the pecking order. If you throw into the mix the likes of Aston Villa's James Milner or Tottenham's Jermaine Jenas, then England are not short of central midfielders.
Capello already has plenty of options. The skill, of course, will be in picking the right blend.
STRENGTHS AND WEAKNESSES
Barry is the type of player who has never been blessed with blistering pace, but as a holding midfielder you do not really need it. He is very good at keeping things simple and retaining possession, which is something that England have failed at in the past.
But there is a lot more to Barry's game than that.
At Arsenal, Patrick Vieira and Emmanuel Petit were capable of doing some great work with the ball, but they also took it in turns to sit in front of the defence and protect the back four. Having that type of player who can work in a crucial area of the pitch we call "the hole" helps relieve pressure on the centre-backs.
At international level, you often get players who operate between the midfield and the defence. It is a huge advantage to have that type of player in your side, as you can see from the graphic above.
The holding midfielder and centre-backs form a little triangle, helping the team avoid being pulled out of position and thus preventing gaps from appearing in defence.
Some teams, like Liverpool or Spain, now like to play with two holding midfield players. There was a degree of that with Vieira and Petit, although Vieira usually had licence to go forward and Petit tended to do the sweeping up.
If England had a fit Hargreaves then he would be the most suited to that holding role
England have had some success when employing Barry and Carrick together in the centre of midfield. They improved the team's second-half display against Egypt at Wembley and worked well together in the 2-1 win over Germany in Berlin in 2008, although both games were friendlies.
In my view, Carrick is not as much of a shield in front of the back four as Barry, so that is why the City man has the advantage. Barry does not come across as a typical ball-winner - like Hargreaves - but you should not underestimate his tackling skills. He closes space down quickly and breaks up attacks.
What Barry and Carrick both have going for them is that they can pass the ball. In that holding position, you need to be good with the ball or have someone close by to whom you can give it.
Take former Chelsea and Real Madrid midfielder Claude Makelele. He was a master of winning the ball and then giving it to the players around him. Barry and Carrick offer a bit more than Makele in that they can create and score goals.
England's opponents in Group C are the United States, Algeria and Slovenia, so Capello might not need to play a holding midfielder at all. You could go for 4-4-2 and be a bit narrower. In that scenario, Milner might come into the reckoning.
But if England opt for an attacking line-up, as Capello seems to prefer, featuring an out-and-out winger like Aaron Lennon on the right, plus Gerrard and Ashley Cole on the left, you need a defensive-minded player to sit in front of your back four to cover.
If England had a fit Hargreaves, then he would be the most suited to that holding role, but in his absence I would opt for Barry ahead of Carrick, who is a very good player to bring off the bench.
You need a game plan but you also need a 'Plan B'. England have that with Barry and Carrick.
Lee Dixon was talking to Alistair Magowan