Let the Saints be canonised again. A decade on from their last Premiership triumph, Northampton are champions of England once more, Courtney Lawes hoisting the trophy aloft before heading to France with one last special Twickenham memory to savour.

Lawes bids adieu after 17 years of sterling service that have seen him evolve from a lithe lock into the most complete blindside flanker in the world. This was a farewell said in fitting fashion to a legend of club and country.

And how Northampton needed his calm and character to survive a final that eddied this way and that. The contest may not have hit the heights some expected, but any fears that the encounter would be flattened by Beno Obano’s 20th-minute dismissal were misplaced. How Bath, down to 14 men for an hour, battled, their brains and bravery unquestioned, even if they were ultimately defeated.

Come the last, George Hendy was Northampton’s unlikely hero, conjuring a wonder try before ripping the ball free from Bath hands in the corner to seal a hard-fought victory that Saints will celebrate long into the summer. This may not have been a performance that they will remember fondly, but there can be no denying they merit this title having led the way for so much of the season and having ended a Saracens era in their semi-final.

The nerves of a rare Twickenham trip seemed to play on the minds of two sides recently untested on this stage. Even Bath’s Finn Russell, who has previously patrolled this place like his own palace, struggled to settle in the opening 20 minutes, the Scottish fly-half’s first strike from the tee an ugly duckling that landed somewhat short and left of the posts.

Russell reset to knock over a simpler chance for the game’s opening score. There was little otherwise, though, to encourage the crowd into the contest; spilled high balls and errors in phase play creating a staccato rhythm. Fin Smith, so calm and consistent across the campaign, tugged his attempted reply to Russell’s opener against the upright – its clang rather encapsulated the opening skirmishes.

A drop goal was more nicely struck by the young Englishman but it was from the restart that followed that the game pivoted. Saints’ Juarno Augustus was the man in receipt of it, setting off on a meandering charge that sent him cutting towards Obano. It looked like the Bath prop was in trouble from the moment shoulder made contact with head. With the officials deeming that there was no mitigation, referee Christophe Ridley reached into his pocket and retrieved a red card.

A hundred seconds later, Northampton capitalised on the extra man. A cleverly constructed move saw Lawes draw two and flick a flat ball to George Furbank, who accelerated up the inside lane. Furbank carried club and country colleague Tommy Freeman, with him and he took his full-back’s pass to the line.

The pair are certainties to be named in Steve Borthwick’s England squad on Monday for the tour of Japan and New Zealand, and Northampton’s second score showed precisely why there is every chance the third member of their back three may well join them. Ollie Sleightholme has established himself as the finest finisher in the Premiership this season, and there was still plenty to do as he collected some neat inside handling on the left. His grubber might have been slightly mishit, but a dash and dot down ensured he capitalised regardless.

It threatened to be a damaging day for Bath, 28 years without a top-flight crown looking ever more certain to go on, but Thomas du Toit punched over from close range to keep them in touch at half-time. Russell brought them nearer still with a crisp three after the interval.

Smith replied in kind but Bath were soon, improbably, level. Hendy had just been introduced for an injured Burger Odendaal and the canny Bath captain Ben Spencer felt it wise to test him with a dainty cross-chip. The considerably larger Will Muir put pressure on the Northampton replacement and was on hand to scoop up the loose change from the fumbling Hendy.

Down again descended the fog of uncertainty, the frets and frustrations of a game now too close to call evident to see. Northampton’s decision-making has been outstanding this season but for periods here it deserted them: Alex Mitchell was mugged venturing down a blind alley, Curtis Langdon knocking on at first receiver having been tossed a nasty, needless pass inside his own 22.

It had been a herculean defensive effort from Bath, though one that was taking its toll. The tremendous Sam Underhill was taken off clutching an ear that looked to be in two bits, disappearing to the dressing room as Russell’s third penalty nudged his side in front. Sat high in the Twickenham stands, Bath owner Bruce Craig – who has ploughed his love and millions into the club for 15 years – was starting to believe.

But the Saints were resurrected with a try sent from heaven. Hendy needed to atone for his error and did so with a graceful gallop, burning by Ollie Lawrence and brushing off two more. An offload off the deck found Mitchell to complete the job, before Hendy made one last vital defensive intervention. Bath had fought to the last but the trophy had to be Lawes’ to lift.