Kansas City's bye week backfired, with the Eastern Conference leader falling to the expansion Montreal.
Felipe Martins opened the scoring in the first half, uncorking from nearly 40 yards. The Brazilian barely had any business considering a shot from that distance, but the left-footed blast swerved around Jimmy Nielsen and in.
Montreal capped an unexpected win with a penalty in the second half.
Lamar Neagle skipped through the SKC backline and Aurelien Collin brought him down. Patrice Bernier stuttered and scored his first goal in MLS, and his first goal for the Impact since 2002.
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