The rain that had been forecast earlier in the week, but the rapture that would greet the final whistle looked a long way off in the first 20 minutes, Saracens doing their best to wash away Saints’ parade.
It took only five minutes for Saracens to get on the score board, Chris Wyles on the end of a slick first-phase move from a lineout on Saints’ 22.
Conceding from a set piece is frustrating enough, but what drew the groans from the crowd was the way that Saints conceded the second, just eight minutes later. Saracens were blitzing in midfield, forcing Stephen Myler to throw something of a hail mary pass in front of his sticks to Christian Day.
More defenders swarmed on the breakdown than attackers, turning over the ball to create the positon for the eventual score.
But Saints had been playing some promising stuff, rewarded by a pair of Myler penalties in the ninth and 12th minutes. And their efforts were rewarded right at the end of the opening quarter, Luther Burrell keeping the ball in two hands to attract multiple defenders and finding Samu Manoa with an accurate off-load for the score.
Myler converted to bring Saints back to within a point, but when he was charged down by Billy Vunipola in the next passage of play a third Saracens try looked all but certain.
However the number eight fumbled while diving over, and while Charlie Hodgson added a penalty to his two earlier conversions there was a strong sense that this could have been a turning point in what was an open and enthralling contest.
And so it proved. Vunipola left the action shortly afterwards, coming back out from the changing rooms with a bulky ice pack on his lower leg, and his replacement Jackson Wray came off almost as soon as he had come on, play having been stopped for a number of minutes so the back rower could receive treatment.
The other Vunipola, prop Mako, had also been having an impact, especially in the scrum, which yielded Saracens multiple penalties.
So it was to their credit that Saints came out in the second half with a new purpose, both to turn around this set piece and impose their structures on the overall game.
That said, it fell to Hodgson to get the first points of the second half, landing a penalty seven minutes after the resumption of play.
But after that Saracens did not get a look in as Saints took full control. The approach play continued to be promising, powerful running and accurate play repeatedly taking Saints downfield to within sight of the visitors’ whitewash.
Saracens held out during Maro Itoje’s yellow card, but their discipline failed them time and again under the pressure that came from the men in red and white, with Myler shrugging off any first-half shakes to land four unanswered penalties inside 19 minutes to both earn him the man of the match bubbly and put Saints into the semi-finals.
SAINTS Tuala; K Pisi, G Pisi, Burrell, Elliott; Myler, Fotuali’i; Corbisiero, Hartley (capt), Ma’afu, Lawes, C Day, Wood, Clark, Manoa
Reps – Haywood, A Waller, Denman, Dickinson, Fisher, L Dickson, Stephenson, Wilson
SARACENS Goode; Strettle, Bosch, Barritt (capt), Wyles; Hodgson, De Kock; M Vunipola, Brits, Johnston, Kruis, Itoje, Joubert, Brown, B Vunipola
Reps – George, Gill, Longbottom, Hamilton, Wray, Wigglesworth, Farrell, Ashton
REFEREE Greg Garner
5mins SARACENS Try Wyles Con Hodgson 0-7
9mins SAINTS Pen Myler 3-7
12mins SAINTS Pen Myler 6-7
13mins SARACENS Try Wyles Con Hodgson 6-14
18mins SAINTS Try Manoa Con Myler 13-14
27mins SARACENS Miss pen Hodgson
31mins SAINTS Miss pen Myler
36mins SARACENS Pen Hodgson 13-17
HALF-TIME SAINTS 13 SARACENS 17
47mins SARACENS Pen Hodgson 13-20
49mins SARACENS Yellow card Itoje (Technical)
53mins SAINTS Pen Myler 16-20
58mins SAINTS Pen Myler 19-20
63mins SAINTS Pen Myler 22-20
72mins SAINTS Pen Myler 25-20
80mins SAINTS Miss pen Myler
FULL-TIME SAINTS 25 SARACENS 20