Desecrating a national symbol is a powerful means of protest or of showing antipathy for a national group, but how do such actions impact ingroup favoritism? We investigated this issue via two field studies conducted prior to the France versus Ireland (Study 1, N = 72) and France versus Germany (Study 2, N = 165) matches at the Euro 2016 soccer tournament. We asked French participants to imagine the ingroup/competition outgroup flag being burnt by ingroup/competition outgroup perpetrators. Imagining the ingroup flag being burnt increased proingroup bias through increase in either ingroup favoritism (Study 1) or outgroup derogation (for all outgroups, including those unconnected with the threat; Study 2). Perpetrators’ group membership did not have the expected moderating effect. We discuss the implications of these results for social identity defense strategies and for the consequences of intragroup versus intergroup threats.