Wales lose star wing
The 25-year-old suffered the injury in the humiliating 13-57 thrashing by two-time European champions Saracens in their opening Champions Cup clash last Sunday.
"George North suffered a sprain to his posterior cruciate ligament against Saracens which will require six-eight weeks rehabilitation," a statement issued by Northampton said.
North, capped 69 times, has become increasingly prone to injuries with the latest coming after he insisted on playing on after receiving treatment following a crashing tackle by Brad Barritt before collapsing to the ground in a subsequent attack.
Wales coach Warren Gatland is due to name his squad for the four Tests on October 24.
His side face the Wallabies on November 11th, Georgia a week later, world champions the All Blacks on November 25, and round off their packed programme against South Africa on December 2.
Agence France-Presse
