Sunderland manager Martin O'Neill says Irish winger James McClean has received death threats after refusing to wear an embroidered poppy on his shirt for a Premier League match.
Police are investigating reports the 23-year-old McClean received the threats on a social networking site.
McClean was the only Sunderland player to appear against Everton last weekend and not wear a jersey with a poppy to commemorate Remembrance Day, honoring those who sacrificed their lives in wars.
Speaking after Sunderland's 3-1 win over Fulham on Sunday, O'Neill says McClean has been criticized for his decision, including "getting death threats as well now, so that doesn't help."
McClean was subjected to abuse on Twitter this year after switching national teams from Northern Ireland to Ireland.