Sporting Lisbon lost Seydou Doumbia under bizarre circumstances on Wednesday when the striker was taken off with an injury after being adjudged to have taken a dive against Barcelona.
Doumbia, 29, latched on to Gelson Martins' pull-back and looked to go outside Gerard Pique on the edge of the area, but instead fell to the ground.
However, his fall only earned him a yellow card for simulation, not a free kick, as Romanian referee Ovidiu Hategan quickly made his mind up that Doumbia had feigned contact from Pique.
In the aftermath, Doumbia remained grounded inside the Barca box and needed treatment from the Sporting medical team.
It was eventually decided that he couldn't play on and, with just a couple of minutes to play in the first half, he was replaced by Bas Dost.
Doumbia joined Sporting on loan from Roma in the summer and had scored one goal in his three appearances going into Wednesday's game with Barca.
It's his fourth loan move in just three seasons, following spells with CSKA Moscow, Newcastle United and Basel.
Former Liverpool defender Sebastian Coates' own goal was the only goal of the game as Barca ran out 1-0 winners to make it back-to-back wins in this season's Champions League.
Ernesto Valverde's side now have six points from their opening two games in Group D matches, while Sporting have three following their opening day win against Olympiakos.