Sporting Lisbon are demanding that Tuesday's Champions League game against Schalke be replayed after they lost to a controversial injury-time penalty.
Jonathan Silva was adjudged to have handled the ball by Russian referee Sergei Kasarev but television replays showed contact was with his head.
Eric Maxim Choupo-Moting converted the penalty to give Schalke a 4-3 victory.
"Sporting have demanded the match be played again or receive the bonus for a draw," Schalke said in a statement.
"Schalke 04 have been asked by Europe's governing body Uefa for their position on the matter and will submit this shortly while taking into consideration the protection of the club's own interests."
Sporting, who played with 10 men from the 33rd minute after Mauricio was sent-off, had come from two goals down to level 3-3 - but they now prop up Group G with one point while Schalke are second with five.