UEFA on Friday said that it was taking action against Denmark's Nicklas Bendtner over his goal celebration against Portugal, when he flashed the waistband of his underpants showing an apparent sponsor.
European football's governing body said in a brief statement that Bendtner was facing disciplinary proceedings for "improper conduct (Law 4 of the Laws of the Game)" during Wednesday's match in Lviv, Ukraine, that Denmark lost 3-2.
"The UEFA Control and Disciplinary Body will deal with this case on Monday," the statement added.
Law 4, which covers "The players' equipment" states: "Players must not reveal undershirts which contain slogans or advertising. A player removing his jersey to reveal slogans will be sanctioned by the competition organiser.
Article 18.18 of the "Regulations of the UEFA European Football Championship 2010-12" also states: "All kit items worn during the final tournament must be free of any sponsor advertising."
The waistband of Bendtner's green and white underwear had the name of a Dublin-based online betting firm. The company, Paddy Power, said on its website that they were "lucky pants".