Luke Shaw suffered an horrific suspected broken leg as Manchester United's return to the Champions League ended in a disappointing 2-1 defeat to PSV Eindhoven.
Luciano Narsingh and Hector Moreno found the net as the Dutch champions recorded a narrow triumph over United in their first Champions League match in 17 months.
But Moreno should not have been on the pitch to head PSV level after Memphis Depay's opener.
With 15 minutes gone, the Mexican slid in with a late two-footed challenge on Shaw in the box.
The England defender was carried off on a stretcher while receiving oxygen eight minutes later. Disturbing replays showed Shaw's right foot bent at a 45-degree angle, which meant he had surely broken it.
Incredibly, referee Nicola Rizzoli did not award a penalty and Moreno was allowed to equalise Depay's stunning solo opener with a header.
Then, just before the hour, Narsingh took advantage of some slack marking from Shaw's replacement Marcos Rojo to finish off a counter attack and give the hosts an historic win that gives them an early advantage in Group B.
Depay was in the mood to show his former employers what they were missing. The Dutchman received a pass from Daley Blind, skipped past Santiago Arias and Jeffrey Bruma before slotting the ball through the legs of PSV goalkeeper Jeroen Zoet.
Any celebrations were short-lived, however, as PSV equalised five minutes later. Moreno shrugged off Matteo Darmian to head in Maxime Lestienne's corner.
The game turned full circle as PSV took the lead after half-time. Lestienne was the provider again. He latched on to a crisp volleyed pass from Andres Guardado and floated a ball over Rojo's head for Narsingh, who nodded in.
