George North will play no part for Saints against Sale on Friday night - and his absence opens the door for Juan Pablo Estelles to make his Aviva Premiership debut.
Estelles, whose only previous Saints action came as a replacement in November’s Anglo-Welsh Cup win at Newcastle, starts on the wing.
The Argentina international secured his place in the starting 15 by scoring two tries for the Wanderers in their 20-11 win against Leicester on Monday night.
As for North, Saints boss Jim Mallinder had said earlier in the week that he could feature for the first time since suffering a head injury at Leicester on December 3.
But the club team release said: “George North has both trained with the squad and undergone a specialist review this week.
“All parties have agreed that North continue with a full training schedule with the rest of the club’s players to ensure he is fully prepared for first team action.”
While North isn’t available, a number of Saints’ other international stars return after being rested for the 60-13 Champions Cup defeat at Leinster last Saturday.
Courtney Lawes, Tom Wood and Louis Picamoles are all back in the starting 15.
There is also a welcome return for lock Christian Day, who has recovered from the head injury he sustained in the Premiership defeat to Newcastle on November 25.
Alex Waller will reach a significant milestone against Sale this week as he lines up to make his 200th Northampton appearance at the age of just 26.
Centre Nafi Tuitavake is named among the replacements and could make his first Premiership appearance.
Meanwhile, Sale have made one change to the starting 15 that lost to Saracens last weekend, with Mike Phillips taking the place of James Mitchell at scrum-half.
Josh Beaumont returns to the match-day 23, and takes his place on the bench, while Kieran Longbottom features in the squad for the first time since October 1.
Saints and Sale are both desperate for points as they currently sit ninth and 10th respectively in the Premiership standings.
Saints: Foden; K Pisi, Burrell, Hanrahan, Estelles; Myler, Groom; A Waller, Haywood, Brookes; Lawes, Day; Wood (c), Harrison, Picamoles. Replacements: Clare, E Waller, Hill, Ratuniyarawa, Gibson, Kessell, Wilson, Tuitavake.
Sale Sharks: Haley; Solomona, James, Leota, Charnley; MacGinty, Phillips; Harrison, Webber, Aulika; Evans, Ostrikov; Neild, Lund (c), Ioane. Replacements: Briggs, Flynn, Longbottom, Beaumont, Mills, Seymour, Mitchell, Arscott.