The referee’s whistle blew and Northampton’s director of rugby, Phil Dowson, flashed up on the big screen, allowing himself a smile. With the clock in the red and Northampton trailing by two points, they had just been awarded a penalty, within range, and such is Dowson’s faith in Fin Smith, he knew his outstanding fly-half would not miss this one.

Perhaps it is time for Steve Borthwick to show a little more faith in Smith because here was another demonstration of the 22-year-old’s talents. He had missed a couple of kicks, needed the help of a post for another but there was little doubt he would secure the victory Northampton so desperately sought, inflicting a first league defeat in seven matches on Bath in the process.

Smith also had a hand in all four of Northampton’s tries and produced arguably the tackle of the match on Miles Reid. He is yet to start for England and though namesake Marcus is the incumbent, Fin’s case is growing stronger by the week.

“Not my best game,” was his self-deprecating analysis but his thought process for the telling kick pulled back the curtain on his mindset. “I wasn’t super confident over it but I have kicked hundreds of thousands of balls in the last five to 10 years so I went back to that. I tried to picture myself at the local rugby club kicking a ball and really relax to block out everything and thank God it went over.”

It was a match Northampton really needed to win to entertain hopes of reaching the playoffs and successfully defending their title – secured by defeating Bath at Twickenham in June – even at this early stage of the year. They romped into a 19-0 lead before Bath blasted their way back and led when Finn Russell’s penalty bisected the posts with just a couple of minutes to go, only for Smith to have the final say. Dowson was fearing the worst after Russell’s penalty – awarded much to the fury of the home supporters as Ollie Lawrence’s response to a high tackle from Alex Mitchell appeared somewhat delayed – but he could breathe a sigh of relief at full time.

“We’ve got to take loads from it. There’s loads we can do better in attack, defence and set piece,” said Dowson, who lost Ollie Sleightholme to a hamstring injury before kick-off in a development which will concern Borthwick. “It was a relief because we’d done loads of good stuff in the game but it got a bit scrappy.”

Northampton struck like a rapier, running the ball from deep or beating the Bath defence with clever chipped kicks or deft offloads. Bath, for their part, tend to bludgeon away with their bruising forwards. Johann van Graan opted for a 7-1 split on the bench, mimicking his fellow South Africans, and given the way Bath turned the screw in the second half, it was a successful albeit a qualified one due to first-half injuries to Guy Pepper and Will Muir. It is a contrast that made for a compelling contest.

Northampton’s first try came inside two minutes and with a touch of fortune. Smith’s long pass just about made it to George Hendy, who gathered and set off on one of his mazy runs before flinging inside to Rory Hutchinson, who shipped on to Josh Kemeny to score. Moments later Northampton were over for their second with Smith again the architect, gathering his chip ahead before Mitchell put Fraser Dingwall over and No 3 came with just 13 minutes on the clock – James Ramm arcing his run through the Bath line.

Bath hit back with tries from Joe Cokanasiga and Orlando Bailey – who profited from a perfectly weighted pass from Russell – but Northampton responded themselves in fine style with the excellent Hendy gathering a left-footed grubber from Smith and dotting down.

Bath added pressure in the second half thanks to their beefed up bench and they were soon over through Will Stuart from close range. A Smith penalty stretched Northampton’s lead to 10 before Bath wrestled control of the match with tries from Max Ojomoh – after a lovely offload from Sam Underhill – and a second for Cokanasiga after Reid had charged down Hutchinson’s hurried kick. Russell’s missed conversion kept Bath’s lead to just two points but Smith spurned the first opportunity to seize back the lead, dragging a penalty wide.

He was on target with the second, however – with some help from the left-hand post – but just missed with his next shot at goal, keeping Northampton’s lead at one. Bath thought they had pinched it when Mitchell was sent to the sin-bin for a high tackle on Lawrence and Russell bisected the posts, only for Smith to win it for Saints. “It was a great advert for the Premiership but I don’t enjoy losing great games,” said Van Graan, who was sanguine in defeat after Bath had outscored Northampton five tries to four. “It goes down to one decision and if that goes the other way you win the game – that’s sport.”