Harlequins prop Kyle Sinckler has been ruled out for the rest of the season with a knee ligament injury.
The 22-year-old tight-head sustained the injury in a tackle by Jacques Burger in the 42-14 defeat by Saracens.
Quins boss Conor O'Shea felt the tackle was dangerous but Sarries forward Burger has not been cited.
"It's massively frustrating because we have an injured player with a bad knee from a no-arms tackle," O'Shea told BBC Radio 5 live after Saturday's game.
Sinckler came through Harlequins' academy and signed a new deal until the end of the 2016-17 campaign earlier this year.
The Wandsworth-born forward, who played for England against Crusaders on their tour of New Zealand last summer, has made 52 appearances for Quins.