Shirts embroidered with the symbol have been commissioned to mark Remembrance Sunday, but the Derry-born winger chose not to wear one during his side's clash with Everton
Premier League players have been requested to wear shirts embroidered with poppies over the weekend in order to pay tribute to servicemen lost in war with Remembrance Sunday approaching.
But Derry-born McClean opted to wear a shirt without the symbol against Everton at Goodison Park and has attracted criticism from observers for his decision.
Sunderland have now moved to underline their commitment to the campaign, describing McClean's snub as a "personal choice".
A Sunderland spokesman said: "As a club Sunderland AFC wholeheartedly supports the Remembrance Commemorations. It was James’s personal choice not to wear a shirt on this occasion."
The 23-year-old has yet to explain the reasoning behind the move.