Changes introduced to promote attacking football, combined with a golden age of strikers, have produced a wonderfully entertaining World Cup.

A proposal for managers to be able to use a fourth substitute in extra time is set to be put before the law-making International Board again.

The idea has been considered before but its value has been enhanced by the sight of so many players struggling to last high-tempo matches at the World Cup finals in Brazil.

A record five of the eight second-round matches stretched into extra time and the potential value of the extra-sub was acknowledged by Gerard Houllier, the former France manager who is heading up FIFA’s technical study group in Brazil.

The TSG is tasked with reviewing emergent trends at major tournaments and reporting back to the world federation and coaches in the autumn.

Some 154 goals have been scored so far, a significant improvement on previous modern World Cups at this stage.

Houllier ascribed this to a number of factors, chief among them “because we have a generation of outstanding strikers” and hailed what had been, “from a football point of view, a great competition so far.”

He also pinpointed that many matches had been decided in the later stages when fatigue was becoming a factor. Hence the possible sense for a fourth substitute.

He said: “It’s an idea we will put to FIFA and FIFA pass on to the International Board then maybe we would have fewer players going down with cramp.

“In this World Cup everything is so fast and tempo has been so high so nearly all the goals have been scored in the final 15 minutes when substitutes play such an important part because they come into the game with fresh legs and attitude: 29 goals by substitutes here is a record.”

Houllier had not been as surprised as some observers at the positive nature of so much of the football. This has been hinted at by the football at last year’s Confederations Cup.

He thought teams had been encouraged by successive refinements to the laws of the game and a stricter interpretation.

Houllier said: “Teams who really go for it are more rewarded now because strikers are protected better than before and the referees are better not only physically but in terms of game reading so nothing escapes a referee now . . . we have the last defender rule, no backpass to the goalkeeper, a lot of rules which have been taken up by FIFA and the International Board which have encouraged positive football.

“Also, we have a generation of outstanding strikers such as Neymar, Messi, Van Persie, Robben, James Rodriguez and many others.”

What had surprised Houllier was the “physical commitment of all the teams.”

He said: “Even the last game of the second round, between Belgium and the US, the US gave everything and could have equalised. That really means something: You have teams who have come to play the World Cup fully and so the physical level and tempo have been raised.

“This is my ninth World Cup and it’s the best one in terms of quality and entertainment.”

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