England could lose a player for disciplinary reasons after centre Piers Francis was cited for a dangerous tackle on the USA's Will Hooley.
Francis caught Hooley with a shoulder-led challenge to the head in the opening seconds of Thursday's 45-7 victory over the Eagles at Kobe Misaki Stadium.
The Northampton playmaker's hearing will take place in Tokyo on a date yet to be determined and he could face a significant ban if the citing is upheld.
England expect to have a fully fit squad available for their World Cup showdown with Argentina after Mako Vunipola and Jack Nowell took full part in training on Friday.
Vunipola and Nowell missed the Pool C wins against Tonga and the USA because of hamstring and knee injuries respectively, but they should be in contention for the Tokyo Stadium clash on Saturday week.
"We trained early this morning and Mako and Jack are good. At this stage we believe everyone will be available against Argentina," attack coach Scott Wisemantel said.
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