"The news on Per is very bad as we're set to lose him for the rest of the season," said Jewell. "Although the scan only showed medial ligament damage, we feared he'd torn his cruciate ligament too.
"Having had the operation the surgeons were then able to look closely at his cruciate and unfortunately that was found to be torn too.
"It's heartbreaking for the lad and we're all devastated for him because he's been a vital part to our fine start to the season."