Sorrell was stretchered off the pitch in the 64th minute and was later found to have suffered an avulsion fracture to the groin (when muscle and bone fragments are pulled away from the bone).
The centre will undergo surgery on Tuesday afternoon and is expected to be out of action for 10-15 weeks.
Saracens coach Rod Kafer was disappointed to hear of the extent of Sorrell's injury as he had only just returned to action after a late start to the season because of a training-ground injury.
"I know that Kevin will be devastated to be out for so long," said Kafer.
"He had just shaken off a niggling pre-season injury and was in the shape of his life and I was looking forward to working with him over the coming months. We will not be looking to replace him as we have cover in place."