"Kyle has an achilles injury but it's not quite as black and white as that," explained Warriors head coach Danny Wilson in The Scotsman. "It's the ligaments in that area and we are trying to nail down what it means.
"He's had a scan and he's got an appointment to see a specialist. It's definitely a medium-termer. Whether we see Kyle again this season, we'll have to wait and see, but at the moment it's doubtful.
"It's unlucky because he has been in really good form and was really looking forward to playing back in South Africa but only lasted around 10 minutes [against the Stormers]. We're disappointed for him and obviously for us because he's been quality and was man of the match against Newcastle recently.
"Sammy Johnson picked up an ankle niggle and we're still trying to see what that means for him for this weekend," Wilson added. "When you add to that Matt Fagerson, Scott Cummings, Rufus McLean, George Horne - these are big international players who you really want to have going into the business end of the season."
Ratu Tagive has flown out to South Africa to provide cover. The winger was scheduled to play for Stirling County - Tagive fractured his cheekbone during pre-season and his playing time has been limited.
"He's been able to play a few games now, and when you think we have lost Rufus, Seb [Cancelliere] and Kyle in a very short space of time, we needed to bring Ratu out here and get him up to speed as quickly as possible, because he's a good player and if he doesn't play here then we are jumping on a flight almost as soon as we get back to go and play Lyon in Europe," explained Wilson.