Saints were sinners at St James' Park as their indiscipline cost them dear against high-flying Newcastle Falcons.
The black, green and gold were beaten 25-22 in a nip and tuck Aviva Premiership encounter that was won largely by the boot of former Leicester Tigers fly-half Toby Flood.
It meant the home fans in the 30,000-strong crowd could celebrate as their team won the game branded The Big One.
For Saints, there was a feeling of real frustration as they continually pegged the Falcons back only to quickly be punished by referee JP Doyle, costing them three points on a regular basis.
Tries from David Ribbans, Rob Horne and Nafi Tuiitavake meant Saints were in with a real shout of only their second away league win of the season.
But the Falcons held their nerve late on to see the game out and strengthen their claims for a play-off place.
The Falcons looked to have got off to a flying start when Chris Harris produced a huge hit on Piers Francis and Sinoti Sinoti picked up the loose ball to race in for the score.
But the TMO was called into action and he deemed Harris had knocked on in the tackle, meaning there was to be no try.
Newcastle did get the scoreboard ticking soon after though as Flood landed a penalty.
The Falcons had flown out of the blocks and more pressure came when No.8 Nili Latu broke away from a scrum and Saints were forced to scramble to stop Sinoti Sinoti out wide.
And Saints then got going at the other end as a slick piece of play carried them to within range and Ribbans picked the ball up from a ruck to barge over for the score.
Myler, who had played a lovely pass in the build-up to the try, was unable to land the conversion amid some noise from the home fans, who were reprimanded by the PA announcer.
Falcons soon reclaimed the lead as Flood landed his second penalty of the day, but Saints were playing some tidy stuff, keeping the home side on their toes with some fast interplay.
But they were not showing the same sharpness in defence and they left the door open for Vereniki Goneva as the wing cleverly picked the ball up at a ruck and glided through a gap to score.
He enjoyed his 50th Premiership score with an Alan Shearer-style celebration at the home of Newcastle United, and Flood's conversion soon made it 13-5 to the Falcons.
It was a harsh scoreline for Saints, who needed to grab the next points in the game to stop the deficit becoming too big before the break.
Flood missed the chance to extend his team's lead with an ambitious penalty attempt from close to halfway and Saints made him pay.
Ben Nutley gathered a high ball and the Falcons then failed in another aerial contest as Horne picked up the pieces, kicking ahead to score.
Myler added the extras to cut the gap to just a single point with four minutes to go until half-time.
But Flood had the final say of the first 40 minutes as he landed another penalty.
And he was at it again at the start of the second half, stretching the Falcons lead to seven points.
Saints were struggling to win the breakdown battle, with penalty after penalty going the way of the Falcons.
But when they did manage to keep possession and put pressure on the Falcons, the home defence was creaking.
Amid a Mexican wave backdrop, Nutley sent a pass wide to Tuitavake after a patient move and the Tongan finished well in the corner.
Myler converted superbly from the touchline to level the scores, but, once again, Saints conceded a penalty straight away, and Flood kicked it to make it 22-19.
But Myler responded with a penalty of his own after a venture into opposition territory from George North.
Flood had an immediate chance to land yet another three points after Nutley was penalised for holding on, but the Falcons fly-half hit the post and Saints breathed a sigh of relief.
Flood had another go soon after, stepping up from long range and just about finding the distance to pick up the points that put his team back in front.
And though Saints continued to scrap for every ball, they could not find a way upfield as the home side shut the door and secured the spoils.
Newcastle Falcons: Hammersley; Goneva, Harris, Matavesi, Sinoti; Flood, Young (Stuart 38); Lockwood, Cooper (Lawson 74), Davison; Green, Robinson (Witty 74); Olmstead, Welch (c), Latu (Hogg 74).
Saints: Tuala (Mallinder 65); Tuitavake (Foden 74), Horne, Francis, North; Myler, Groom (Reinach 56); Ma'afu (van Wyk 63), Haywood (Marshall 74), Brookes (Ford-Robinson 74); Ratuniyarawa, Day (c); Ribbans, Gibson (Eadie 38), Nutley.
Referee: JP Doyle