Leicester Tigers boss Geordan Murphy admitted Saints' back row were too intelligent for his team at Welford Road on Friday night.
Jamie Gibson, Heinrich Brüssow and Teimana Harrison all had a huge influence as Tigers were tamed on their own turf.
Saints secured a superb 29-15 success at the home of their local rivals, with Tom Collins' double and Cobus Reinach's opener setting them on their way.
Dan Biggar added 14 points with the boot on a fantastic night for the Wales fly-half.
And Murphy was left to reflect on a chastening defeat for his Tigers team.
“We had our chances in the first half and we bombed them," Murphy said.
"I thought Saints did a really good job of slowing our ball down and they had some pretty good threats over the ball.
“I thought they were really intelligent the way they did that, Teimana Harrison was great, Jamie Gibson and Heinrich Brussouw – right on the line of legality.
“It was a strange game.
"We started with a great intensity and made a couple of poor mistakes which cost us territory then Saints scored a great try from a breakaway and we were chasing the game from there.”
Tigers are now just nine points above bottom side Newcastle Falcons, who host Sale Sharks at St James' Park this evening.
And Murphy said: "We need to drive forward and get more out of ourselves, me included.
"We want to be competing at the top end of the league, but we are right down at the bottom and in the mire.
"It's going to be tight. We have struggled with our confidence all season."