Saints had showed their intent from the off, Noah Cato making a powerful tackle right from the kick off and backs and forwards going through the phases well.
A penalty was the result, and although Stephen Myler had the range the direction was off and the hosts survived. Whether they would have done so had Saints' number 10 not taken a knock while running the ball is up to question; but Nick MacLeod had no such excuse three minutes later when his own shot at the sticks also went wide.
The balmy late summer conditions were certainly making for some entertaining rugby with both sides willing to throw the ball around. But there is a time for picking when to run and when to use the boot, and Joaquin Tuculet's decision to do the former proved misjudged when he became isolated, held on in the tackle and handed Myler the chance to open the scoring, which he duly did.
Saints were more picky when they chose to put the ball through the hands, one Martin Roberts break setting up some pacy pick-ups at successive rucks and Paul Diggin coming off his wing to ask questions of the home defence.
Myler's kicking out of hand was excellent, too, and he also showed he was back on form from the tee by landing a 17th-minute penalty from nigh on the halfway line.
Saints had not had everything go their own way by any means, and twice their right touchline had come in very useful in helping stop a pair of dangerous Shark attacks, the first a David Seymour charge from close range, the second a Will Addison break from deep that forced a desperate attempt from the last defender to force him into touch.
But when Saints caught a break they made the most of it. The scrum had set up Saints' second penalty, and when MacLeod's kick off sailed straight into touch the power came on again and Myler duly made it 9-0.
MacLeod made amends two minutes later with his first success, and in truth the score was deserved for an attack that took Sale to within a couple of metres of the visitors' whitewash.
But this only seemed to spur the visitors onwards. Roberts showed his attacking threat with a quick tap and go and Samu Manoa came within a couple of inches of his maiden try for the club.
The confidence was visibly running through the Saints, and when a further penalty came in front of the sticks there was no hesitation in opting for the scrum. But while the power was seemingly there on tap the visitors just could not quite keep it turned on for long enough. Dwayne Peel's frustration earned him 10 minutes in the sin bin, but his team mates held out not just the subsequent drive but the attack from the base and when the ball was turned over to be booted upfield the Edgeley Park faithful applauded their team wholeheartedly.
Only time would tell whether these few minutes would go on to be a turning point. Saints had shown the ability to cause problems, but the Sharks had demonstrated the dogged determination that had earned them wins over London Irish and Wasps in Rounds 2 and 3.
Overall, however, it had been an encouraging 40 minutes from the Saints. But with still just six points between the teams as the second half got underway more of the same was very much needed from the men in white.
Things started well enough, Sale's initial charges being held out and Myler putting James Downey through a massive hole with some neat footwork. The Lancastrian, who was born just half-an-hour's drive from Edgeley Park, also maintained his good night with the boot as well, landing a fifth penalty.
However MacLeod had also shaken off his first kick blues, and his own third success meant that with 10 minutes gone nothing had really changed in terms of the margin on the score board.
That said, Saints were looking threatening with the ball, Manoa making his now trademark charges and Tom May running dangerously up the right wing. But with the killer touch remaining frustratingly elusive it was left to Myler to extend the lead with yet another three-pointer.
At 18-9 the contest was far from over, and when Sale took advantage of a wayward lineout to score through Mark Easter the momentum looked like swinging suddenly in the hosts' favour.
The try had come completely against the run of play, but when Calum Clark was yellow carded for a late tackle on MacLeod Sale had the bit firmly between their teeth and 10 minutes to take advantage of the extra man.
Things went from bad to worse when Phil Dowson followed his team mate to the sin bin for kicking the ball away, and with MacLeod making it a one-point ball game Saints looked like they were in danger of throwing the game away from a position of dominance.
The dam finally broke with Clark waiting on the sidelines to come back on, Peel finishing off a period of home dominance that featured a 15-metre maul that had rolled inexorably towards the line.
The one saving grace was MacLeod's kicking, which was single-handedly keeping Saints in the game. His two missed conversions meant that with 10 minutes to go the visitors returned to full strength just the four points down.
Myler made the most of a home indiscretion to make it 22-21 to set the stage for a humdinger of a finish. But Sale had other ideas and when Seymour crossed unopposed the contest was over.
REFEREE Tim WIGGLESWORTH
4mins SAINTS Miss pen Myler
7mins SALE Miss pen MacLeod
9mins SAINTS Pen Myler 0-3
17mins SAINTS Pen Myler 0-6
20mins SAINTS Pen Myler 0-9
22mins SALE Pen MacLeod 3-9
29mins SALE Yellow card Peel
37mins SAINTS Pen Myler 3-12
39mins SALE Pen MacLeod 6-12
HALF-TIME SALE 6 SAINTS 12
45mins SAINTS Pen Myler 6-15
47mins SALE Pen MacLeod 9-15
55mins SAINTS Pen Myler 9-18
58mins SALE Try Easter 14-18
59mins SAINTS Yellow card Clark
62mins SAINTS Yellow card Dowson
63mins SALE Pen MacLeod 17-18
68mins SALE Try Peel 22-18
72mins SAINTS Pen Myler 22-21
75mins SALE Try Seymour Con MacLeod 29-21
FULL-TIME SALE 29 SAINTS 21