Jamie Gibson has revealed that Saints interim head coach Alan Dickens told the players to shape up or ship out during their defeat to Sale Sharks on Saturday.
The black, green and gold were 31-6 down at half-time after conceding four first-half tries, three of which were scored by England wing Denny Solomona.
Saints stepped things up after the break, scoring three tries of their own, through Michael Paterson, Rob Horne and Heinrich Brüssow.
But it was nowhere near enough as Sale saw the game out to secure a 34-25 success, which was their first win in Northampton since May 2006.
After the game, flanker Gibson, who came on during the first 10 minutes for the injured Tom Wood, was asked what was said at half-time.
He replied: "Alan Dickens came in and he effectively reiterated what he said before the game but in slightly more angry terms.
"There was no hair-dryer treatment and he said 'boys, you can go home and pack your bags or you can step out on the pitch, try to make a difference and see what you can come up with 40 minutes to go'.
"We answered those questions there, but it's still a massive disappointment in the end."
On the game itself, Gibson said: "The first half was unacceptable.
"We came into the game on the back of a couple of good performances. We lost at Exeter last week, but in many ways it was one of the best performances of the season.
"To come back home and with the effort everyone has put in to clear the snow, we had a chance to hit a good Sale side hard and we failed to do it.
"Forty minutes, you give them 30 points and there are not many teams who can come back from that in this league.
"We felt second half we took control of the game, but in the first half, we were chasing shadows."