The Kiwi scrum-half is making good progress in his recovery from a knee injury picked up in the European win over Clermont Auvergne last month and the Ospreys say he could be back on the field in early to mid- December.
The news will go a long way to easing the region's injury crisis in the No. 9 jersey, with British & Irish Lions star Mike Phillips and Tom Isaacs currently on the long-term casualty list.
While the Magners League clash with Munster at the Liberty Stadium on December 5 may be a bit early for the New Zealand A cap, Nutbrown is on the road to making the flight out to face Italian opponents Viadana in the European Cup on December 12.
The Ospreys have been mulling over bringing in another scrum-half as short-term cover, but with Rhys Webb having returned to action against Bath earlier this month and Liam Davies and Rhodri Wells also available, director of coaching Scott Johnson suddenly has options at half-back.
"Jamie is approaching five weeks since his injury and has shown excellent signs in his recovery," said Ospreys physio Chris Towers.
"We'll be looking to build him back up over the next two to three weeks and will hopefully see him available for selection in early to mid-December."
Elsewhere on the Ospreys injury front, back-rower Ben Lewis has returned to full fitness after his latest knee operation.
Lewis underwent keyhole surgery last month after only just coming back from two major knee ops.
The 23-year-old last played for the Ospreys against Munster in April 2008.
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