The Red Devils had started the Champions League clash in Germany well and were holding the Bundesliga giants until disaster struck.
With 28 minutes on the clock, Leroy Sane cut in from the right and played a one-two with Harry Kane.
He then unleashed a first-time shot from 20 yards upon receiving it back but it was only low and central.
But instead of producing an easy save, United goalie Onana somehow managed to let the ball through his grasp and into the net.
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