On me 'ead son: Why are so many headers being scored at Euro 2012?

A 'true' ball, certain sides – not just England – defending deep and fifth officials watching for blocking has revived an old art

Maybe those gentlemen on the goalline, Michel Platini's fifth officials, are finally having an effect. They may not have been able to spot the penalty the Republic of Ireland should have been awarded on Sunday when Robbie Keane was tripped, but their very presence seems to be inhibiting defenders at his year's European Championship.

At the last World Cup, 26 of the 145 goals were scored with headers, just less than 18 per cent. Two years on, and including the three headers which were netted in last night's Portugal versus Denmark game), 12 of 30 goals (a staggering 40 per cent) were from headers. In addition Russia's opening goal against Czech Republic was driven in by Alan Dzagoev after Alexsander Kerzakov headed against the woodwork.

This was not expected. Headed goals have been critical in three of the last six finals of the Euros, but these days, everyone is supposed to ape Barcelona, a team of magnificent midgets who only put the ball in the air when Lionel Messi scoops it over the goalkeeper. Instead the ghost of Nat Lofthouse appears to be stalking Poland and Ukraine.

This is a small sample, and may be a statistical freak, but there do appear to be several reasons. The most basic is that the ball appears "true". The over-hit crosses that were a familiar sight in South Africa two years ago, with the Jabulani beach ball, are a rarity. In addition players have been able to familiarise themselves with Tango 12, the ball having been shipped to the competing nations in December.

There is more to it, however, than better delivery into the box. What happens when the ball arrives is key. We have become used to defenders grappling and manhandling attackers as a cross comes in, to "blocks" being made as forwards attack the ball. Some defenders do not even follow the ball, they simply watch their man. This time, however, the wrestling has been largely absent. With an extra official stationed on every goalline, there seems a greater reluctance to cheat in this way – it may be teams have also been warned referees will crack down on such offending.

Blocks, too, seem less in evidence. Indeed, ITV's Jim Beglin criticised the Poland defence for not blocking Dzagoev's run before he headed in Russia's goal on Tuesday. Players are instead getting a clear run at the ball: four of the headed goals have been scored direct from set-pieces with another after a corner had been partially cleared, but the goal area was still crowded.

Then there is the pattern of the matches. In the opening round, several teams – notably England, Portugal, Ireland and Sweden – spent much of the match defending the 18-yard box in banks of four. This was a largely successful attempt to prevent teams passing through them, but it has two consequences.

Opponents are forced to go round them, and send crosses in. Also the defence tends to drop deep which means opposing strikers can head from close range. Three goals have been a result of this with the third Croatian goal against Ireland a classic example (albeit that it went in off the post and Shay Given's head). Ireland's defence was just outside the six-yard box when Ivan Perisic crossed, enabling Mario Mandzukic to head from less than 10 yards out.

Will the trend continue? Or will defenders start to wrestle at set-pieces and coaches tell their back four to get up the pitch? Alternatively the likes of Andy Carroll, Olivier Giroud and Fernando Llorente will be telling their coaches that the increase in headed goals means "this could be my tournament, so get me off the bench and in the team".

Heads we win: 12 goals (and counting) off bonce

1. Robert Lewandowski (Poland v Greece)

Byline cross from full-back

2. Mario Gomez (Germany v Portugal)

Deflected cross from deep

3. Mario Mandzukic (Croatia v Ireland)

Deflected cross from byline

4. Sean St Ledger (Ireland v Croatia)

Free-kick crossed from deep

5. Mario Mandzukic (Croatia v Ireland)

In off post and goalkeeper

6. Joleon Lescott (England v France)

Free-kick crossed from deep

7. Andrei Shevchenko (Ukraine v Sweden)

Cross from advanced wing position

8. Andrei Shevchenko (Ukraine v Sweden)

Near-post flick from corner

9. Alan Dzagoev (Russia v Poland)

Free-kick crossed from deep

10. Pepe (Portugal v Denmark)

Near-post flick from corner

11. Nicklas Bendtner (Denmark v Portugal)

Point-blank nod-in

12. Nicklas Bendtner (Denmark v Portugal)

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