Saracens flanker Jacques Burger has been cited for alleged foul play during last Sunday's European Champions Cup quarter-final game against Racing Metro in Paris.
European Professional Club Rugby said that Burger is alleged to have struck Racing scrum-half Maxime Machenaud midway through the match at Stade Yves-du-Manoir, which Saracens won 12-11.
The complaint was made by match citing commissioner Eugene Ryan.
Namibia international Burger, 31, will face a disciplinary hearing on Thursday. Welshman Simon Thomas has been appointed as independent judicial officer.
World Rugby's low end punishment for such an offence is a two-week ban, with anything from eight weeks to 52 weeks at the top end.
Saracens return to Aviva Premiership action against play-off rivals Leicester on Saturday, before tackling Champions Cup semi-final opponents Clermont Auvergne in Saint Etienne on April 18.
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