It was something of an unforgettable afternoon of rugby from the Saints, highlighted only by a penalty try that edged them in front seven minutes from time and littered with errors and a lack of continuity, something they would have hoped to eradicated from defeat last Friday night at Harlequins.
The Saints made a probing start but it was Irish, with an attacking spell of their own who took the lead when Tom Mercey took out a lineout jumper allowing Tom Homer slotted the 35-metre penalty with confidence. The hosts were quickly level though, Lamb thumping over from just inside halfway after a careless tackle from Chris Hala'ufia on Paul Diggin.
There was a chance for Irish to take the lead once more and although Homer's place kick cannoned back off the upright, the bouncing ball eluded the Saints' grasp. Fortunately for them, a second huge shove of the day turned over an Exiles scrum and allowed Lamb to clear with a penalty.
Martin Roberts was looking lively for the Saints, twice carving through gaps and while his enterprise and another scrum against the head provided good attacking platforms, two the ball slipped from the Saints' grasp in Irish territory.
The visitors were really struggling to cope with Roberts, the Welsh scrum-half bounding clear once again like a pinball and after an onslaught on the Exiles line, Lamb doubled his and the Saints' tally with a second penalty of the afternoon, almost followed immediately by a third as Leo Halavatau took a yellow card for his team's persistent defensive misdemeanours.
It was to prove a first missed place kick of the season for the Saints though, Lamb's curling effort striking a post before Irish scrambled the ball out of play to signal the end of the half.
The visitors survived the remaining sin bin time relatively well, Saints guilty at times of trying to force the play, and would in fact level the game up as they returned to a full contingent, a Homer penalty from straight in front the score.
His next effort was rather more challenging as the young fullback chanced his arm from the half way line. While it was a chance missed, Homer looked to have the range and it would certainly have acted as a warning to the Saints.
What followed was simply put - destruction. Rampaging all afternoon, Hala'ufia used nothing more than brute force to plough through a gang of Saints tacklers and with the big number 8 offloading well too, play was spread to the waiting Nick Kennedy to cross unopposed in the right corner.
Tension was building amongst the Saints supporters, helped little by a Stephen Myler penalty that started on target, but baffled the replacement 10 by drifting wide. Passes were going to ground, eluding runners or marginally forward for the Saints and the clock was starting to tick down.
When the offer of points came around, the Saints instead went to the corner through Myler and the decision was almost validated as the Saints pack rumbled over the Irish line. With no conclusive evidence that the ball had been grounded, it was instead scrum-five and when the set-piece collapsed twice, there was no doubt about the result as referee Martin Fox headed straight underneath the posts. Myler's conversion snatched the lead and now it was Irish who were chasing the lead against the clock.
The visitors were patient in attack and when the chance came, Homer wasn't going to let it up. The crowd were none too pleased with what they thought was a knock on, but it mattered little as among a chorus of boos the posts were bisected. All that was left was to collect the restart and having done so successfully, Dan Bowden was free to run the ball into touch and end a miserable afternoon for the Saints.
TRAVIS PERKINS MAN OF THE MATCH Chris Hala'ufia
REFEREE Martin Fox
8mins IRISH Pen Homer 0-3
11mins SAINTS Pen Lamb 3-3
17mins IRISH Miss pen Homer
38mins SAINTS Pen Lamb 6-3
40mins IRISH Yellow Halavatau
40mins SAINTS Miss pen Lamb
HALF-TIME SAINTS 6 IRISH 3
51mins IRISH Pen Homer 6-6
54mins IRISH Miss pen Homer
55mins IRISH Try Kennedy 6-11
60mins SAINTS Miss pen Myler
73mins SAINTS Try Penalty Con Myler 13-11
79mins IRISH Pen Homer 13-14
FULL-TIME SAINTS 13 IRISH 14