If there were any lingering doubts about Northampton’s ability to ­sustain a title push they can be ­unequivocally put to bed after a mighty victory over Saracens. Five tries, an intensity that went missing last week and a masterclass at fly-half from Fin Smith tightened their hold on top spot of the Premiership, and gave their sellout crowd reason to believe this will be their year.

They were thumped last week as the league resumed after an eight-week break and their 10-match ­winning run was unceremoniously broken by Bristol, who ran in 52 points. Could Northampton respond? They did so emphatically against last season’s champions who were not at their imperious best – none more out of sorts than Owen Farrell, who was eclipsed by the supreme Smith.

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It is to Saracens’ credit that they scrapped until the end and finished with four tries after scoring from two charge downs and twice at the death through Alex Lewington to earn what could prove a pivotal bonus point in the playoff race. That Northampton were still ultimately resounding winners in a ferociously competitive encounter will only boost their confidence, however.

Tommy Freeman scored the pick of Northampton’s tries as they ­produced an attacking edge that could breach even the toughest defences. If they continue in this vein they will take some stopping between now and June. It helps, too, when they show this type of resilience and all the more so to have 21-year-old Smith in this kind of form, kicking 16 points and showcasing an all-round game to put Farrell in the shade. If the Saracens fly-half represents England’s past as he prepares for life across the Channel next season then Smith is the future.

“That speaks volumes about the character of the group,” said ­Northampton’s director of rugby, Phil Dowson. “We were all disappointed last week and the response was clear to see.”

Jack van Poortvliet (pictured) scored on his return to the starting XV as Leicester Tigers beat winless Newcastle Falcons 19-13 after remarkable late drama at Kingston Park.

The scrum-half dotted down after Brett Connon had given the hosts an early lead from the tee before Ben Redshaw and Julian Montoya traded tries for each side.

Another Connon penalty restored the Falcons’ narrow lead, but Ollie Hassell-Collins flew down the left wing to hand the Tigers their fourth win in five Premiership games – but not before they had to see out 15 minutes of added time with players in the sin bin.

"I don't think you'll see another game like that in any hurry where it's 97 minutes deep – crazy," said Dan McKellar, the Tigers' director of rugby.

A lightning-quick start meant the scoreboard read 7-3 to the Tigers after just five minutes – Connon nailed a 45-metre penalty from just left of centre to open the scoring, only for Van Poortvliet to mark his first start in the Premiership this season with a driving run through the middle of the home defence for the first try of the evening.

Redshaw put the Falcons back in front on 17 minutes with an excellent run, breaking through with 25 metres to the post before Connon added the extras.

The seesaw scoring continued as the men in green and white went over against the run of play – Montoya dotting down after a maul.

Connon had the first major opening of the second period with a 40-metre penalty from centre, but he kicked wide of the posts. He made no mistake on 63 minutes with a much simpler task to give the north-east side the lead again.

However, it did not last long as Hassell-Collins found space on the wing and scored, with Handré Pollard finding his range with the boot from out wide to extend the lead to six points with 14 minutes left to play.

Late yellow cards for the visitors’ Charlie Clare, Freddie Steward and James Whitcombe left them with 13 men for much of the added time and briefly down to 12, and extended the game long enough for Steward – sin-binned in the 84th minute – to return for the final moments.

The Tyneside club, though, could not find a way back despite a succession of scrum penalties inside the Tigers’ 22.

McKellar added: "We've got to be better in a lot of areas, there's no doubt, but you've also got to give credit to the opposition as well. They've made some changes up here and I wouldn't be looking forward to being [one of the] teams that still has to visit Kingston Park." PA Media

Saracens had scored a half century of their own last week so Northampton’s performance was all the more impressive. They made seven changes with Courtney Lawes ­captaining the side and whatever he said in his pre-match team talk had the desired effect.

Launching on to the front foot they had two early tries, the first from Alex Coles after a delightfully disguised pass by Smith, the second for James Ramm after a breathless run from Ollie Sleightholme, who beat six defenders only for the seventh to pull him down just short of the line.

Smith’s penalty gave Northampton a 17-0 lead – no less than they deserved – but Saracens got a foothold when Theo McFarland charged down Tom James and pounced on the loose ball to score. A Farrell penalty brought Saracens to within touching ­distance and their aerial ­bombardment brought enough joy that it was ­Northampton who were most ­grateful for the half-time whistle.

Another Farrell penalty from straight in front of the posts brought Saracens back to within four points but Ramm raced over for his second try of the game after an attack sparked by James’ quickly taken penalty – ­Northampton injecting a tempo into the game that their visitors could not live with.

In fairness to Saracens, few teams can when Northampton play with this kind of pace and another Smith penalty extended their lead further. Indeed, Saracens were clinging on at times but another charge down, this time from Ben Earl on Ramm, handed his side a second try and another route back to within seven points. Their task was made all the more difficult, ­however, when Lewington was shown a ­yellow card for a deliberate knock-on and when the resulting penalty was kicked to the corner, Northampton whipped the ball through the hands and Freeman, coming off his wing, finished off the bonus-point try.

The fifth try came through Sleightholme, who picked up the loose ball near the halfway line and ­scampered clear to put the result beyond doubt. But Saracens refused to throw in the towel and scored two late tries through Lewington after Smith had been somewhat harshly sent to the sin-bin. They move up to second as a result of their bonus point and while this has not been a vintage season by their ­standards, they will not give up their title without a fight.