Fabien Lemoine appears set for a lengthy spell on the sidelines, but will not be going under the knife.
The Rennes midfielder took a hefty blow to his back during Saturday's 3-0 win over Nancy, forcing him from the field.
He was rushed to hospital when it became apparent his injuries were serious, and tests revealed that he had suffered kidney damage.
The 23-year-old is now on the road to recovery, having been given the all-clear, but is still set to miss up to six months of the season.
"It is too early to say exactly how long he will be out, but the news is more reassuring than it was on Sunday," said Rennes' general manager Pierre Dreossi.
"Contrary to what was first forecast, Fabien will not be needing surgery. That would only have been an option had he been bleeding."
Lemoine's absence will be keenly felt by Rennes as he has become an integral part of their first-team plans since making the step-up into the senior fold back in 2007.