Also included in the squad is Coventry City goalkeeper Michael Quirke, who receives his first Republic of Ireland international call-up, as does Preston midfielder Adam Barton, who previously made an appearance for Nigel Worthington’s Northern Ireland senior team in a friendly against Morocco last November.
King said: “This friendly is a key element to our preparation for the European Championships which begin on September 1 at home to Hungary in Sligo. We have made a number of changes, purely to look at as many of our players as possible ahead of the campaign.
“Portugal are a talented side and include players such as Manchester United star Bébé and their recent 3-1 victory over Sweden proves that they will be a big test for us,” added the Ireland boss.
Squad: I McLoughlin (Stockport, on loan from Ipswich), M Quirke (Coventry City), R Towell (Hibs, on loan from Celtic), S Duffy (Everton), G Gunning (Motherwell, on loan from Blackburn), S O’Connor (Ipswich), R Kiernan (Wycombe, on loan from Watford), D McCrory (Dagenham & Redbridge), A Barton (Preston NE), M Connolly (Bolton), C Henderson (Arsenal), J Devitt (Hull City), S Scannell (Crystal Palace), C Clifford (Chelsea), J Collins (Shrewsbury), J Mason (Plymouth), P Madden (Carlisle Utd)