Watch: Fullkrug catches PSG napping for emphatic goal

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All it takes is one lapse in concentration to get punished.

Paris Saint-Germain's backline fell asleep for just a second in Wednesday's clash with Borussia Dortmund, and Niclas Fullkrug made them pay with the opening goal of the Champions League semifinal tie.

The burly German striker ghosted behind the PSG defense, took down a long ball in stride, and ripped a wicked low shot beyond goalkeeper Gianluigi Donnarumma to give Dortmund a 1-0 lead in the first leg.

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