Shane Drahm justified Paul Grayson's decision to select him, he weighed in with a try, a conversion, two penalties and a drop goal.
With coach Budge Pountney exiled in the stand serving a touchline ban for calling referee Steve Lander 'a disgrace' a fortnight ago, Paul Grayson directed operations from the dugout.
Leicester had an off day, with a number of errors spoiling their momentum, and each and every one was punished by the Saints.
First number eight Henry Tuilagi lost control of the ball at the back of a defensive scrum, and Johnny Howard stole the ball to put Drahm over from close range in the third minute.
Neil Back was sin-binned in the 13th minute for wrapping up the ball at the bottom of a ruck, as Leicester simply tried to do too much.
Drahm punished that offence with a penalty, then drilled over a left-footed drop-goal before Vesty's 21st-minute penalty got the visitors on the board.
Then it was Bruce Reihana's turn to get into the act from full-back, surging down the blindside and putting wing Rudd in for the second Northampton try in the 24th minute, with Drahm converting.
THe intensity of a local derby started to get to both teams with former England captain Martin Johnson and Saints prop Simon Emms both shown the yellow card for fighting off the ball.
Drahm's second penalty edged the hosts further ahead before Leicester finally got a foothold in the game with their first try.
Vesty slipped Lloyd through a midfield hole to the line, then added a penalty at the end of the half to ensure the Tigers only trailed 21-11 at the break.
Leicester duly reverted to a route one offensive after the break, playing for position and launching their familiar driving mauls from lineouts.
But they could not find the control they normally enjoy, and they were restricted to just one attempt on goal which Vesty missed from kickable range in the next 20 minutes.
Their afternoon was summed up when they won two penalties on halfway. Austin Healey found touch with neither.
And it was completed when Tuilagi threw a stupid panic stations pass, Cohen managed to squeeze over, and Franklin's Gardens exploded into rapture.
For Northampton:Tries: Drahm, Rudd, CohenCon: DrahmPens: Drahm 2Drop goal: Drahm
For Leicester: Try: LloydPens: Vesty 2
Northampton Saints: 15 Bruce Reihana, 14 John Rudd, 13 Neil Starling, 12 Marc Stcherbina, 11 Ben Cohen, 10 Shane Drahm, 9 Johnny Howard, 8 Andrew Blowers, 7 Corné Krige (captain), 6 Darren Fox, 5 Damien Browne, 4 Matt Lord, 3 Robbie Morris, 2 Dan Richmond, 1 Simon Emms.Replacements: 16 Chris Budgen, 17 Brett Sturgess, 18 Grant Seely, 19 Mark Soden, 20 Billy Fulton, 21 Luke Myring, 22 Wylie Human.
Leicester Tigers: 15 Seru Rabeni, 14 John Holtby, 13 Leon Lloyd, 12 Daryl Gibson, 11 Austin Healey, 10 Sam Vesty, 9 Scott Bemand, 8 Will Johnson, 7 Neil Back, 6 Henry Tuilagi, 5 James Hamilton, 4 Martin Johnson (c), 3 Darren Morris, 2 George Chuter, 1 Michael Holford Replacements: 16 James Buckland, 17 John Rawson, 18 Luke Abraham, 19 Louis/Brett Deacon, 20 Roger Warren, 21 Dan Hipkiss, 22 Alesana Tuilagi
Referee: Ashley RowdenTouch judges: Ashley Reay, John PearsonTMO: Gary Welsh