BBC Sport pundit Keith Wood says Ireland prop Cian Healy's stamp on England's Dan Cole during the hosts' 12-6 Six Nations defeat in Dublin was "nasty".
Former Ireland captain Wood adds that he thought it was halfway between a yellow and a red card, although he believes Healy will be banned.
Ex-Scotland scrum-half Andy Nicol says Healy "knew what he was doing" and that he expected the player to get a straight red.
Healy will appear before the tournament's disciplinary committee in London on Wednesday.
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