Harlequin centre George Lowe will miss the remainder of the season as a result of the injury he suffered in the match with Saracens on September 28.
Lowe, 24, injured his neck while making a tackle early in the game. He was taken to hospital for assessment and was discharged and returned home.
However, further scans and guidance from specialists over the past four weeks has revealed more extensive damage and he had been advised not to play again this season.
The club said he will "undertake a programme of treatment that aims to have him fit to return to action for the 2014-15 season".