The 29-year-old limped off in the first half at the Lamex and now faces an extended spell on the sidelines.
“George’s injury looks a serious one which is a shame for him,” said Wrexham boss Phil Parkinson. “It was an innocuous incident, the lad has almost fallen on him and we really feel for George. It looks like he is facing a lengthy spell on the sidelines.”
Centre-back Max Cleworth also damaged ankle ligaments against Leyton Orient last week and whilst his injury is not as bad, he appears unlikely to feature this weekend.
“George’s is a lot more serious than Max,” added Parkinson. “We are just waiting for the swelling to go down with Max before we can give a definitive timescale on when he will be back.”
Ollie Rathbone (thigh) has returned to training and will be assessed ahead of Saturday’s game. Wrexham will be looking to make it five wins from five at home when the Cobblers visit.
“It will be good to be back at The Racecourse,” added Parkinson. “We are pleased with the start to the season we’ve made at home, we have been good and we are looking forward to continuing that.
“We always respect the opposition. Northampton have had a couple of bad results at home but it is about us regrouping and resetting as a team after the defeat on Tuesday.”