Harlequins inflicted a blow on Northampton's charge towards the Guinness Premiership with a tight 13-6 win at the Stoop on Saturday.
Title-chasing Northampton arrived having won six Premiership games in a row to face a Harlequins team still recovering form a dreadful 46-6 hammering at Gloucester, their third consecutive league defeat.
And the visitors came armed with three members of the England squad, Ben Foden, Chris Ashton and Courtney Lawes, whereas Quins were without the inspirational Nick Easter who is part of manager Martin Johnson's starting XV to face Ireland next week.
The hosts took the initiative, running at Saints from the start, and were rewarded with a third-minute penalty for not releasing, scored by fly-half Nick Evans.
But tempers were up very early with a series of scraps testing referee Doyle's mettle.
One flare-up turned a Quins scrum into a penalty against Juandre Kruger, scored by Evans after seven minutes.
Northampton's first venture into Harlequins territory earned a penalty on 10 minutes following a pulling down in the lineout offence, awarded against James Percival. But Stephen Myler's kick sailed yards wides.
From the restart, Harlequins returned to the visitors' 22 where only solid defence prevented the game's opening try. Northampton were fortunate not to go 9-0 down when referee Doyle awarded a scrum rather than a penalty with two Saints clearly offside at a ruck.
Northampton's management looked decidedly unimpressed with their scrummaging during the first quarter, but they had to be relieved with the defence as Lee Dixon got underneath a certain try by George Lowe after he'd shot across the line.
But there was no stopping Quins, and from the scrum, the ball was worked towards the left where Lowe drew the cover before passing out to Mike Brown who thundered over. A fine angled conversion by Evans saw the hot favourites 13-0 behind after 20 minutes.
Harlequins were as sharp as they've been all season, and continued to play most of the first half in Northampton's last third.
The 12,935 crowd played their part, generating a thumping atmosphere, and when Evans flipped a superbly-timed pass towards former England wing David Strettle, his fumble feet from the line let the visitors off the hook.
And when Saints finally broke out to earn a penalty seconds from the interval, Myler again fired wide.
Northampton made a far better start to the second half, but when presented with the chance to cut the deficit just two minutes in, Myler completed a hat-trick of missed penalties. He finally broke his duck on 46 minutes when Doyle penalised Quins for offside.
And when presented with yet another pot at goal in the 55th minute, Myler doubled Northampton's score, and put them right back in the game.
Evans had the chance to calm home nerves with his team's first kickable penalty of the half, but scuffed his 64th minute kick and watched as it fell short.
But Shane Geraghty, on for Myler, did no better three minutes later, firing a kickable penalty across the face of the goal.
Pens: Evans 2
Pens: Myler 2
Harlequins:15 Mike Brown, 14 David Strettle, 13 George Lowe, 12 Jordan Turner-Hall, 11 Tom Williams, 10 Nick Evans, 9 Karl Dickson, 8 Tom Guest, 7 Will Skinner (c), 6 Chris Robshaw, 5 Lewis Stevenson, 4 James Percival, 3 John Andress, 2 Chris Brooker, 1 Ceri Jones.
Replacements: 16 Matt Cairns, 17 Aston Croall, 18 James Johnston, 19 Tomas Vallejos, 20 Chris York, 21 Steve So'oialo, 22 Rory Clegg, 23 Sam Smith.
Northampton:15 Ben Foden, 14 Chris Ashton, 13 Jon Clarke, 12 James Downey, 11 Paul Diggin, 10 Stephen Myler, 9 Lee Dickson, 8 Phil Dowson (c), 7 Neil Best, 6 Courtney Lawes, 5 Juandre Kruger, 4 Ignacio Fernandez Lobbe, 3 Euan Murray, 2 Brett Sharman, 1 Soane Tonga'uiha.
Replacements: 16 Andy Long, 17 Brian Mujati 18 Darren Morris, 19 Mark Easter, 20 Scott Gray, 21 Alan Dickens, 22 Shane Geraghty, 23 Chris Mayor.