Leicester and England fly-half Toby Flood has been cited for an alleged 'tip tackle' in Friday night's Aviva Premiership clash against Worcester, the Rugby Football Union have announced.
Flood will face an RFU disciplinary hearing on Tuesday.
Any period of suspension would leave him in grave danger of missing Leicester's pivotal Heineken Cup pool games against the Ospreys and Toulouse later this month.
The second-half incident, which saw Flood tackle Worcester fly-half Andy Goode, went unpunished on the field.
But RFU citing officer Shaun Gallagher has now reported him.
Owen Farrell currently occupies the England fly-hald role, but Flood remains a key part of red rose head coach Stuart Lancaster's plans.
England launch their RBS 6 Nations campaign against Scotland at Twickenham on February 2.
Leicester beat Worcester 19-14 to move top of the Premiership, but their Heineken Cup quarter-final hopes will almost certainly rest on them beating both the Ospreys and Toulouse.
And that task would be infinitely tougher without premier goalkicker Flood's services.
The RFU also announced that Leicester centre Matt Smith had received a written warning for use of the elbow on Worcester centre Alex Grove. The warning is treated as a yellow card for the purposes of totting up this term.