Saints produced a blistering first-half showing to see off struggling Sale Sharks in fog-ridden conditions at Salford City Stadium.
Scores from Jamie Elliott, Soane Tonga’uiha and replacement Tom May as well as 12 points from the boot of Ryan Lamb put Jim Mallinder’s men out of sight at 27-3 up at the break.
And though Sale, now with just one league win to their names after the first 10 games of the season, got two tries after the break through Rob Miller and Tommy Taylor, Saints edged it.
But the away side will be ruing the failure to secure the full five points on a night when they systematically dismantled their opponents early on but took their foot off the gas.
The return of international stars Ben Foden, Dylan Hartley and George Pisi made a big difference as composure was rediscovered early on.
Though there remains plenty to work on ahead of the vital Heineken Cup double-header against Ulster in the next two weeks.
Sale suffered two big blows before the game began as Danny Cipriani and Johnny Leota were unable to take their places in the squad.
MacLeod took over kicking duties and Miller came in on the wing, with Mark Cueto switched to centre.
It was Saints who made the brighter start amidst the Salford fog, which threatened the game at one stage as visibility was poor, with Foden getting them on the front foot with an early surge.
His desire to attack was eventually rewarded as Saints squeezed an early penalty out of their opponents and Lamb booted his side into a 3-0 lead.
But it didn’t take too long for the Sharks to find their feet and MacLeod accepted the chance to pull his side level with a penalty.
It wasn’t level for long, though, as Saints surged forward and a good hands from scrum-half Martin Roberts and prop Brian Mujati helped Elliott fly over in the corner.
Lamb added the conversion to make it 10-3 and the away side had done what they set out to do: put the strugglers under early pressure.
And they turned the screw further moments later after turning the ball over in mdifeld, giving Tonga’uiha the chance to trundle over the whitewash.
Lamb booted Saints into a 14-point lead before adding another three points to the tally with a well-worked drop goal.
The Sharks threatened to show some bite as MacLeod broke the Northampton line, but the returning Foden was lying in wait and put in a trademark block to prevent the try.
In the land of music legends Oasis, he was proving to be Saints’ wonderwall at 15.
The Sharks were sinking fast and replacement May added to their misery, showing some blistering pace to get away from the defence and touch down.
Lamb’s successful conversion made it a massive 27-3 half-time lead for Saints but the Sharks had a try back just after the restart as a fine series of play saw Miller dart over the tryline.
The score narrowed the gap to 19 points and the deficit was further reduced as Saints were penalised for not rolling away and MacLeod landed the resulting penalty.
Northampton were shocked into life and immediately mounted a surge towards the Sharks’ line from the restart but Lamb’s errant drop goal gave away possession.
Mallinder had seen enough as he switched his half-backs, bringing Stephen Myler and Lee Dickson on with 20 minutes to go.
But it was the Sharks who were to get the final score of the game as Taylor used his power to get over the line.
Saints had done enough in the first 40 minutes to secure the victory and are unlikely to be delighted with their second -half showing, which saw them pass up the chance of maximum points.
But the win further strengthens their position in the Premiership top four and leaves Sale with a big task in their fight for survival.
Sale: Shepherd; Amesbury, Cueto, Tuitupou (Uys 26), Miller; Macleod, Peel (Cliff 40); Harrison (Lewis-Roberts 62), Taylor, Buckley (Cobilas 62); Gray, Myall (McKenzie 57); Powell (Gaskell 65), Seymour, Vernon.
Replacements: Ward, Addison.
Saints: Foden; K Pisi, G Pisi, Waldouck (May 26), Elliott; Lamb (Myler 60), Roberts (Dickson 62); Tonga’uiha (A Waller 65) , Hartley (Haywood 74), Mujati (Doran-Jones 63); Manoa, Sorenson; Clark (Oakley 70), Dowson (Nutley 77), van Velze.
Referee: Geraint Roberts