It will have hurt before kick-off when they lost George Hendy, one of the better performers at Sale six days earlier, to injury in the warm-up.
It will have hurt when a forward pass prevented them from extending an 11-point lead with Gabriel Ibitoye in the sin bin.
It will have hurt when Bristol cut that 11-point lead to just one with a penalty and converted try all in the space of a couple of minutes before the break.
It will have hurt when Tommy Freeman, not long after bagging the bonus-point try, went down in pain and eventually went off the field, before later leaving the Gardens wearing a protective boot.
It will have hurt when Harry Thacker scored against Saints yet again, taking his tally to seven against the black, green and gold.
It will have hurt when James Ramm and Sam Graham both limped off the field late on, taking Saints’ injured list past 15 players.
And it will have really hurt when Bristol celebrated late on, with a last-gasp Saints fightback ending with a knock-on.
Saints took only two points from a fixture that they really needed the full five from if they truly are harbouring top-two hopes as they say they are.
But best laid plans don’t factor in the kind of injury curveballs that a team can be hit with during a season.
And even the strongest of squads would be unable to cope with the effects of the men Saints have missing right now.
How deep into the well they are having to go was illustrated by the set of backs they finished with on Saturday afternoon.
Archie McParland, Fin Smith, Tom Seabrook, Rory Hutchinson, Tom Litchfield, Jake Garside and James Grayson were the players it was composed of.
And it is no slight on those players to say that would be very different from the kind of seven Saints would select if they had everyone available.
Still though, the fact those men were left to chase the game late on owed much to some things Saints could, but failed to, control.
They should never have let Bristol back into the game when Ibitoye was sin-binned.
Saints did score early on during the yellow card period but then it seemed to be that Bristol actually started to assume some control with 14 men.
So much so that when Ibitoye came back on, they were able to pounce for those 10 crucial points before the break.
Saints’ lack of discipline in defence was nothing sort of shocking as the Bears were able to extract points on almost every visit to the home 22.
It gave them a platform on which to build and it remains real worry that Saints struggle so badly to relieve the pressure when the heat comes on in defence.
At Sale six days earlier and late on in this match, Saints were met by stern defensive resistance, but that is something that they have struggled to show under the greatest pressure.
They were better in that department at Sale, though they did still allow the Sharks to score 20 first-half points from very few visits to the 22.
And it remains the case that the black, green and gold do not make teams work hard enough to pick up points.
Watch how elite teams like New Zealand and South Africa defend in squeaky-clean fashion under the greatest pressure.
They force the opposition into mistakes or they win penalties at the breakdown to take the heat off.
Saints find it tough to do that, and they got no rewards at the breakdown against Bristol, so often being penalised.
It was a truly painful experience, to watch them up against it and struggling to find a way out.
And how it will have hurt the coaches to have seen their side suffer defeat in a home game they will have expected so much more from.
The agony doesn’t end there as it will now be a case of who Saints can select, rather than who they can choose to select, at Newcastle Falcons next Sunday.
They appear badly depleted and that is a huge concern with so many crucial league games lying in wait.
With just 18 Premiership encounters this season, you really can’t afford to fall too far behind.
And Saints will have to seriously rally whichever troops they have at their disposal this week to ensure they prevent another painful afternoon.
How they rated…
JAMES RAMM – started superbly, setting up two scores for Tom Seabrook and looking like a man of the match contender once again, but he was forced to limp off… 7
TOMMY FREEMAN – grabbed yet another try and looked dangerous when he got his hands on the ball, but was struck down by an injury that could keep him out… 7
TOM LITCHFIELD – a strong showing from the centre as he came in at the last minute and was later labelled ‘excellent’ by boss Phil Dowson… 7
RORY HUTCHINSON – certainly didn’t shy away from the physical battle against some big call carriers… 6
TOM SEABROOK – added another two tries to his ever-growing tally as he showed, once again, that he knows his way to the line… 7
FIN SMITH – kept going for his team, trying to assert himself, and also produced a kick assist for Freeman’s try… 6
TOM JAMES – fired a lovely pass to Pearson for a first-half try but lost his way a little as the game went on… 5
ETHAN WALLER – stood out against Sale but Saints were met with plenty of resistance up front here… 5
CURTIS LANGDON – performed well at Sale on the previous weekend but had a tougher time here and the lineout was an issue for Saints… 5
TREVOR DAVISON – delivered a couple of decent carries but was part of a wholesale front-row change early in the second half… 5
ALEX MOON – worked as hard as ever but Bristol didn’t shy away from contact and kept him quiet… 5
ALEX COLES – tried to produce some power for his team but Bristol handled him well and stopped him from having a say… 5
ANGUS SCOTT-YOUNG – couldn’t really make the impact he would have desired here… 5
TOM PEARSON – grabbed a try as he found a nice line and glided over, but was not favoured by the referee at the breakdown… 5.5
SAM GRAHAM – the skipper started strongly but had a more difficult second half, earning a yellow card and then being helped off the field with an injury… 5
Replacements (who played more than 20 minutes)
ALEX WALLER (for E Waller 50) – looked good in his cameo at Sale, and certainly tried to add some presence in a young side, but Bristol held firm… 4.5
ROBBIE SMITH (for Langdon 50) – got his hands on the ball on a few occasions but couldn’t make any inroads… 4.5
ELLIOT MILLAR MILLS (for Davison 50) – thundered forward once or twice but Bristol dealt with him better than Sale did on the previous weekend… 4.5
JAKE GARSIDE (for Freeman 53) – a tough ask to come into a game in which the Bears were taking control, and didn’t have any chances to show his ability… 4.5
CHUNYA MUNGA (for Moon 54) – looked busy and tried to disrupt the visiting forwards but it was a tough job… 5