Injured duo Courtney Lawes and Dylan Hartley are among nine players released by England ahead of this weekend’s Aviva Premiership action.
But the pair, who sustained knee injuries in Saints’ defeat to Saracens last weekend, are unlikely to play any part in Saturday’s game at Leicester Tigers.
The forwards are to be reassessed by the England medical team at Pennyhill Park on Sunday, having been released as part of a co-ordinated programme between the national team and Saints.
There is some good news for Northampton in that back row Phil Dowson is available to line-up against the Tigers at Welford Road after also being released.
Lee Dickson and Tom Wood are the only Saints players retained by England ahead of the first autumn international against Fiji on Saturday, November 10.
Meanwhile, Leicester have received a double boost as scrum-half Ben Youngs and centre Anthony Allen have been given the go-ahead to play against Saints.
England boss Stuart Lancaster said: “It has been a busy few days of training as well as injury assessment and in line with the EPS agreement coordinating the release of players, some will return for further treatment from their club and others to get some game time to put a marker down for selection for when we meet again on Sunday after the weekend’s games.
“We will not finalise selection for the Fiji game until after training next Tuesday and so for those going back and playing this is a real opportunity to stake a claim with a really big performance.”