Referee Richard Kelly sent off the Jersey professional after a clash with Cambridge back-rower Darren Fox, who was shown a yellow card.
The club’s two-week suspension runs up to Monday, 28 November, when Hannay is due to face a Rugby Football Union disciplinary hearing over the incident.
The decision to invoke an immediate suspension was made at a meeting attended by JRFC chairman Bill Dempsey, head coach Ben Harvey and Channel Islands’ disciplinary officer Cliff Chipperfield.
