Why are so many World Cup goals being scored late?

Caleb Yirenkyi scores Ghana's 95th-minute winner against Panama in Toronto [Getty Images]As the clock ticked towards the final quarter hour of Switzerland's match against Bosnia and Herzegovina, the two teams were locked in a stalemate.Then everything changed. Substitute Johan Manzambi came off the bench and needed only three minutes to score. By the final whistle he had two goals, Switzerland had scored four times after the 70th minute, and Bosnia became only the third team in World Cup history