After watching a superb first-half performance in which their side scored three tries, the majority of the home fans would have expected the Saints to go on and record a comfortable bonus-point win. But due to grit and determination from Bath and their own ill-discipline, the Saints could muster no more points in the second period but still held on for victory.
Director of rugby Jim Mallinder admitted his frustration in the post-match press conference, and it was easy to see why. The errors that had been a nuisance in the first 15 minutes came back with a vengeance after the break as the hosts pushed for the fourth try.
Saints' relatively slow start had allowed Bath to take the lead with an Olly Barkley penalty, but 16 minutes in the sell-out crowd was delighted as the first try of the afternoon went to the hosts. Powerful runs from both Courtney Lawes and Vasily Artemyev brought the Saints up to the Bath line and as quick ball was worked out wide Phil Dowson was on hand to go over in the left-hand corner.
Suddenly the momentum of the game had changed and it wasn't long before the second try was on the board. A beautifully weighted kick over the top from Lamb found George Pisi and as the Samoan man of the match raced towards the line he offloaded superbly to Tom Wood who was able to run over unchallenged to give the Saints their second score in the space of just four minutes.
The quick running and thinking from the Saints was starting to look too much for Bath to handle and just after the half-hour mark Nick Abendanon was yellow-carded for killing the ball. From the resulting penalty Lamb extended the gap between the sides, and try number three wasn't far away either as Saints immediately made their numerical advantage count with some more impressive play.
Bath were struggling to keep Saints at bay as they rampaged towards the line but the ball eventually found Jamie Elliott out wide and he, despite juggling the ball for a second, went over in the corner.
Lamb continued his near-perfect record from the tee to put Saints into a deserved 21-point lead as they received a standing ovation going in for their half-time chat.
As they had in the first half, Bath were handed an opportunity for points within the opening two minutes after the resumption of play. Referee David Rose spotted a high tackle and Barkley duly slotted his second penalty of the afternoon from just outside the 22.
Bath were soon down to 14 men again when Stephen Donald killed the ball between his own sticks, but unlike the first half Saints failed to find the killer touch. Elliott had a try ruled out for a marginally forward pass, and while they had been clinically going through the phases before the break both forwards and backs were perhaps guilty of trying that bit too hard to keep the ball alive.
Then momentum threatened to swing Bath's way. As they got back to their full complement of players Saints saw two players go the other way to the sin bin in as many minutes as first Samu Manoa and then James Downey were shown yellow.
The visitors took advantage straightaway as their forwards barged their way over the line, captain Francois Louw grounding the ball between the sticks. Barkley was successful with conversion and the West Country side were back in the game.
Despite lacking in numbers, Saints then missed two chances to extend their lead as firstly Lamb pushed a penalty to the right of the posts before Pisi came within inches of grounding a ball that was coming down over his head from a neat Lamb chip over the line.
Both sides continued to push for a bonus point in the final 10 minutes of the encounter. Frustratingly neither could find the extra score that they were looking for and the final whistle blew to confirm the victory that pushed the Saints back into the play-off places going into the festive break.
REFEREE David ROSE
AVIVA MAN OF THE MATCH George PISI
14mins BATH Pen Barkley 0-3
16mins SAINTS Try Dowson 5-3
20mins SAINTS Try Wood Con Lamb 12-3
31mins BATH Yellow Card Abendanon
31mins SAINTS Pen Lamb 15-3
34mins SAINTS Try Elliott Con Lamb 22-3
HALF-TIME SAINTS 22 BATH 3
42mins BATH Pen Barkley 22-6
46mins BATH Yellow Donald
60mins SAINTS Yellow Manoa
62mins SAINTS Yellow Downey
64mins BATH Try Louw Con Barkley 22-13
65mins SAINTS Missed Pen Lamb
FULL TIME SAINTS 22 BATH 13