Jim Mallinder says Saints shot themselves in the foot in their defeat to Sale Sharks on Sunday afternoon.
Mallinder was disappointed with the concession of what he labelled ‘two silly tries’ as the Sharks secured a 20-13 victory at the AJ Bell Stadium.
Saints have still not won at the ground in the Aviva Premiership since November, 2012, losing their past three league games at Sale.
And only 13 points from fly-half Stephen Myler, including a second-half try, provided any consolation in their latest reverse.
A first-half score from Sam James and a second-half effort from Will Addison, allied with 10 points from the boot of fly-half Danny Cipriani, secured the win for Sale.
And Mallinder said: “It’s very disappointing.
“We’ve not got a brilliant record up here and we knew it was going to be difficult against Sale.
“They play to a certain style up here and are very difficult to beat, but we sort of shot ourselves in the foot really.
“When you concede two silly tries like we did, you’re always fighting an uphill battle.
“We came back into the game pretty well and we were a better side in the second half, but that’s no consolation when you lose a game.”