Chris Ashton has officially been cited for two incidents of alleged biting against Northampton.
The winger is expected to face a minimum 10-week ban if found guilty of the offence.
The incident occurred in the first half of an incident-packed and fiercely physical match at Allianz Park on Saturday, which Saracens won 27-12. Waller complained immediately to referee Greg Garner.
The low-entry point for the suspension is 12 weeks, a mid-range offence 18 weeks and the top end starts at 24 weeks, any of which would leave Ashton in danger of not playing for the Premiership and European champions again this year.
However, Ashton was banned for 10 weeks last season for making contact with the eyes of an opponents – another offence which has a low-entry point of 12 weeks – and may have his sentence reduced again if he is found guilty.