Harlequins have been hit by a misconduct complaint following an incident during their Heineken Cup quarter-final defeat against Leinster last month.

And the Guinness Premiership club now face a disciplinary hearing that could result in them being fined or even suffer a possible points deduction.

Quins, through their second-placed Premiership finish, have already qualified for next season's Heineken Cup as one of seven English representatives.

Roger O'Connor, European Rugby Cup's disciplinary officer, launched an initial investigation into circumstances surrounding the second-half blood substitution of Quins replacement Tom Williams and fly-half Nick Evans' resulting return to the playing field.

New Zealander Evans had limped off in the 47th minute, before his replacement Chris Malone was then helped off hurt.

Evans though, reappeared after Williams departed late in the game, with television footage appearing to show Williams winking as he left.

Evans, Harlequins' principal kicker, rifled a late drop-goal attempt wide as Quins bowed out of Europe, beaten 6-5 at the Twickenham Stoop.

O'Connor's probe included gathering statements from match officials, the two teams involved and a review of broadcast footage from the game.

He has now made his decision that the matter should go further, and will present the case against Quins.

A disciplinary committee will be convened on a date yet to be announced.

Quins, meanwhile, saw their season come to an end two days ago with their 17-0 Premiership play-off defeat against London Irish.