Valencia coach Unai Emery was sent off for protesting against the decision, with Zigic running over to the goal-line referee to show off his shirt, which had an enormous hole across his chest.

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Then came the controversial moment when Lampard's strike from the edge of the penalty area struck the underside of the bar and bounced down about two feet over the goal-line, only for Uruguayan referee Jorge Larrionda and his assistants to fail to award a goal.

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If the system detects that the ball has crossed the goal line a central computer transmits a signal to the referee via either a watch or earpiece.

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If it crosses the goal line, then an encrypted radio signal is sent to the referee's wristwatch to indicate a goal has been scored.

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It looked like Gary Bollan's run to the goal-line had prevented Combe being the last man, but referee David Somers still showed the goalkeeper the red card.

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