Forrester faces a Rugby Football Union disciplinary hearing next Tuesday following a report from independent citing officer Alan Mansell.
If the case is proved, then England Saxons squad member Forrester can expect a ban ranging from anywhere between two and 24 weeks.
Blair suffered damaged ribs during Sharks' 20-19 Guinness Premiership victory over Gloucester at Edgeley Park last Saturday after seemingly taking a knee in his back.
He is unlikely to play again before March, joining a lengthy Sale casualty list that currently includes the likes of Charlie Hodgson, Jason White, Mark Cueto, Andrew Sheridan and Lee Thomas.
Scrum-half Richard Wigglesworth took over the number 10 duties from Blair just before half-time and kicked a decisive late penalty as Sale ended a run of three successive league defeats.