Eddie Jones has backed Dylan Hartley following criticism of the England captain's recent form for Saints.
Hartley has not been on the winning side at his club since September - the green, black and gold have slipped to 10th in the Aviva Premiership standings - and on his last two outings his opposite number has been named man of the match.
Former England stars Lawrence Dallaglio and Austin Healey were scathing of the Saints skipper's performance in Saturday's 50-21 defeat to Harlequins, but Jones believes his captain is still indispensable.
"It's been a tough time for him," England boss Jones said.
"When you are captain of a club that is struggling, a club that has just sacked their coach, it becomes a difficult time.
"That has been reflective of his play, but very good players do compartmentalise things and he's done that terrifically well, come in and led with effervescence, trained well - he's been good.
"I don't watch club rugby to assess them on how they play at clubs. I watch club rugby to assess how they are going to play at international level, which is completely different.
"Some guys can be outstanding club players and be poor at international level. Some guys can be poor club players and outstanding international players.
"Dylan's attitude is right, his body is right and he brings something to the table that we need at the moment, which is strong leadership."
Saints' new coaching consultant Alan Gaffney, who began his role on Monday in the wake of Jim Mallinder's departure on December 12, has also given the 31-year-old his full support.
"Dylan has been a figurehead here for a long, long time and has a lot of respect among the players," Gaffney said.
"I have not spoken to Dylan since I've been here - he had gone into camp by the time I arrived on Sunday - but I spoke to Eddie about him and he has got the utmost respect for him. I don't see things changing here.
"Northampton has been his club, always has been his club and his heart lies here. I don't see any changes being made there."