Liverpool goalkeeper Simon Mignolet was an unused substitute as Belgium reached the quarter-finals of the World Cup in Brazil with a 2-1 extra-time victory over the United States.

Although the commitment and work-rate of the two sides was faultless, both were guilty of wasting opportunities throughout a goalless 90 minutes at the Arena Fonte Nova in Salvador, forcing a period of extra time.

Within two minutes of the restart, Marc Wilmots' Belgium gained an advantage; a long dribble by Romelu Lukaku eventually created a chance for Kevin De Bruyne, who calmly drilled low into the left corner.

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Provider and finisher swapped roles seconds before the extra-time break, De Bruyne rolling an inviting pass from the left channel into the path of Lukaku, who rifled unstoppably home with a fierce, left-foot blast.

Just when the cause seemed lost for Jurgen Klinsmann's determined team, though, substitute Julian Green connected with a sublime Michael Bradley delivery and coolly volleyed into the back of the net.

But USA could not find an equaliser, despite incessant exertions, meaning Mignolet and his country progress to a mouthwatering quarter-final against Argentina in Brasilia on Saturday.