|Northampton (27) 40|
|Tries: Naiyaravoro 2, Harrison 2, Haywood Cons: Grayson 3 Pens: Grayson 2 Drop-goal: Grayson|
|Harlequins (8) 22|
|Tries: Murley 2, Robshaw Cons: Herron 2 Pen: Smith|
Taqele Naiyaravoro and Teimana Harrison scored two tries each as Northampton Saints brushed aside Harlequins for a third straight Premiership win.
Naiyaravoro scored his brace in the first half, with Harrison's first and Mike Haywood sealing a bonus point.
Captain Harrison added his second try to settle the game after the break.
Caden Murley and Chris Robshaw responded for Quins but, despite Murley's second score, they could not salvage a try bonus of their own.
Harlequins had their chances to get back into the game after half-time but were unable to convert good territory into points and slipped to a second defeat of the season.
Several injuries completed a bad night for the club in a week when they parted company with forwards coach Alex Codling.
By contrast, Northampton's season continues to grow and they have now claimed 14 from a possible 15 points in the Premiership, scoring 102 points in three games.
They won this game in the first 40 as Naiyaravoro took Rory Hutchinson's pass and bounced off three defenders to touch down, before he picked off a loose pass from Quins full-back Aaron Morris to sprint 25 yards into the corner.
Taylor dotted down a loose ball after Tom Collins' charge over the line before Haywood scored Saints' fourth try on his return after a year out with a knee injury, driven over in a rolling maul.
Hutchinson's break from quick line-out ball helped seal the five points as Harrison was worked into the right corner with 15 minutes remaining.
Northampton forwards coach Phil Dowson told BT Sport:
"We started really well and held that pressure until just before half time and then it was battle.
"In the second half we made lots of errors which made it difficult for us but we're very pleased to get the five points."
Harlequins head of rugby Paul Gustard:
"Disappointing isn't a strong enough word I guess, we feel a lot of pain.
"To concede five tries, the manner of them isn't necessarily what hurts the most, it's the fact we've shopped 40 points, we're Harlequins and we don't ship points like that.
"We just didn't keep the ball for long enough and we made too many errors.
"Some aspect of our play were better, but for the most part we lost the physical battle, we lost the urgency battle, and you can't do that against a good team like Northampton."
Northampton Saints: Furbank; Collins, Hutchinson, Symons, Naiyaravoro; Grayson, Taylor; Franks, Haywood, Painter, Ribbans, Moon, Wood, Gibson, Harrison (capt).
Replacements: Van Vuuren, Waller, Hill, Ratuniyarawa, Coles, Tupai, Dingwall, Sleightholme.
Sin-bin: Alex Coles
Harlequins: Morris; Ismaiel, Marchant, Tapuai, Ibitoye; Smith, Landajo; Lambert, Elia, Kerrod, Lewies, Symons, Chisholm, Robshaw (capt), Dombrandt.
Replacements: Baldwin, Auterac, Collier, Lamb, Bothma, Mulchrone, Herron, Murley.