World Cup: How technology is helping minnows strangulate big teams

New tech and resources for studying opponents are letting World Cup minnows cramp the style of bigger teams, Roberto Martinez said as his Belgium side prepare to try and break down a well-organised Tunisia on Saturday.

"It's normal. I think we'll see it more and more in every tournament," the Spanish coach told reporters when asked why some of the world's biggest names, including Brazil, Argentina and Germany, were struggling against modest opposition this year.

"Everyone now has the technology and the information to prepare games down to detail. Many years ago you used to go to a World Cup and it was a surprise on the day and talent and decisions on the pitch made a bigger difference," he said.

"You see every team, that they are on the pitch with a clear idea of what they do," he said, citing a statistic that more than half of all goals in the tournament have been scored after set-pieces.

• Coverage: FIFA World Cup 2018

"It's harder and harder and harder to score goals from open play.

"It's down to the improvement of technology and information and tactical awareness that big teams have to prepare against," he added, particularly noting the recent successes enjoyed by tiny Iceland.

Martinez, however, said he was not preparing with a special focus on scoring from set-pieces, even if both England's goals in their opening 2-1 win in Group G win came from them.

England, whom Belgium will face next Thursday, are strong at the dead ball -- "they have fantastic movement and fantastic delivery," Martinez said -- but he saw no particular weaknesses from Tunisia at set-pieces.

After a 3-0 win over Panama on Monday, Belgium hope to find space to stitch up qualification but will go into the game with respect for Tunisia, who performed well in their build-up to the competition against strong European sides.

Equally, Martinez knows that the opposition will have to open up and play for a win to keep alive their hopes of staying in Russia.

"We respect Tunisia and [their] threat," Martinez said. "But they need to win the game and will be really really open."