While celebrating one of his two goals against Paulo Bento's side, the attacker raised his shirt and revealed underwear with the name of bookmakers Paddy Power blazoned across them.
|THE GOAL LINE | EPISODE NINE
|Layla Anna-Lee presents our latest show, as James Goldman previews Friday's Group D matches
An official statement on the association's website read: "Uefa has today announced that disciplinary proceedings have been opened against Denmark's Nicklas Bendtner for improper conduct (Law 4 of the Laws of the Game) at the Uefa Euro 2012 Group B match against Portugal in Lviv on Wednesday June 13.
"The UEFA Control and Disciplinary Body will deal with this case on Monday."
The game versus die Mannschaft kicks off at 20:45CET on Sunday.