Gloucester's New Zealand prop Greg Somerville faces more than two months out of the game after undergoing eye surgery.
Somerville was hurt during his first start for the club in last Saturday's 42-12 Guinness Premiership defeat against leaders London Irish.
He has now had an operation at a Cheltenham hospital to re-attach the retina in his left eye, and is unlikely to play again before the end of February.
It means the All Blacks forward will miss several Premiership games, in addition to Gloucester's crucial remaining Heineken Cup pool clashes against Cardiff Blues and Biarritz.
Gloucester head coach Dean Ryan said: "It is unbelievably bad luck, not only for Greg but for the squad.
"Everyone was looking forward to working with him at this crucial stage of the season.
"Our thoughts are with Greg because this is a nasty injury and will take some considerable recovery time.
"He is at a new club and desperate to make an impact for us, on and off the field as a player and a leader.
"We will obviously miss his contribution as a world-class player, and we wish him well for a speedy recovery."
Somerville, 31, made his Gloucester debut as a replacement against Calvisano in the Heineken Cup a fortnight ago, before his first start at the Madejski Stadium.Reuse content