Former World Cup referee Graham Poll has expressed his belief that Netherlands keeper Tim Krul was unsporting in his side's penalty-shootout win over Costa Rica.

The Newcastle United keeper was brought onto replace first-choice stopper Jasper Cillessen for the spot kicks and made two crucial saves to guide his side into the last four of the tournament.

However, Poll feels that approaching every Costa Rica penalty taker before their kick was taking sportsmanship too far, and action should have been taken by referee Ravshan Irmatov.

He wrote in his column in the Daily Mail: "While Tim Krul has been hailed as the hero for Holland in the quarter-final penalty shootout his antics as Costa Rica players approached to take their kicks went beyond gamesmanship.

"After standing by the assistant referee while his team are taking their kicks, as the law requires, he should have been made to go straight to the goal to face the next spot kick.

"When he did not, Krul should have been warned and then cautioned for unsporting behaviour if he had ignored the referee. If he had carried on his antics he could have been sent off."

The Netherlands face Argentina in their semi-final clash on Wednesday.