Ireland flanker Sean O'Brien will miss his side's Rugby World Cup quarter-final clash against Argentina after being suspended by World Rugby.

Rugby's governing body handed the 28-year-old the one-match ban after he struck Pascal Pape during his side's final Pool D game against France.

O'Brien was not punished during the game, but was cited for the punch and will now miss his team's showdown against the Pumas.

World Rugby said in a statement: "O'Brien admitted committing an act of foul play and therefore the independent judicial officer Terry Willis upheld the citing. The Judicial Officer deemed the act of foul play merited a low-end entry point of two weeks."

Ireland will also be without Paul O'Connell due to a hamstring injury, which has forced him into early retirement.