Fergus McFadden has been cited for an alleged headbutt during Leinster's Pro14 clash with Ulster on Saturday and will miss the Heineken Champions Cup final against Saracens if found guilty.
McFadden conceded a penalty in a flashpoint with Reidy during Ulster's 14-13 victory at Kingspan Stadium, though referee George Clancy dished out no further punishment at the time having reviewed the incident with the TMO.
Clancy told the TMO at the time: "From what I can see is that he’s leaned into his opponent in an aggressive manner but we can’t see exactly where he has made a connection."
That, however, is not the end of it for the winger, who has been cited and faces a very anxious wait to find out his fate. If found guilty, he faces a minimum six-week ban, which would prematurely end his season and involvement in the province's European and Pro14 charges.
Leinster take on Sarries at St James' Park in Newcastle on 11 May.
"The player has been reported by the citing commissioner in charge for infringement of Law 9.12 - a player must not physically abuse anyone - striking with the head," a Pro14 statement said.
"The player will face a disciplinary committee via video conference, the make-up of the committee will be confirmed in due course."