Saracens overcame a slow start to score five tries and secure a 38-27 victory over Northampton in a thrilling Gallagher Premiership encounter at Franklin's Gardens.

In a game which swung back and forth, two tries in three minutes from David Strettle late on secured a bonus-point win for Mark McCall's men.

The visitors claimed the spoils despite seeing Jamie George and Billy Vunipola yellow-carded in either half as Alex Lewington crossed for a brace with Ben Spencer also on the scoreboard.

Northampton's points came via Piers Francis, Dylan Hartley and Ben Franks, but the boot of Dan Biggar was not enough.

Saints shipped 33 tries in four games against Saracens last season, but welcomed back England captain Hartley for his first start since January.

McCall's defending champions included Hartley's international team-mate Vunipola at number eight and Alex Goode began the game at fly-half with Owen Farrell nursing a minor strain.

Saints dominated the early territory – giant wing Taqele Naiyaravoro made one powerful break – and the home side turned down a series of kickable penalties to go for the try.

Concerted home pressure resulted in Saracens hooker George seeing yellow for collapsing a maul and a Northampton try arrived soon after.

From a scrum, Cobus Reinach picked up and fed Francis who powered to the line. Biggar converted.

Saracens' discipline was uncharacteristically poor and when they were penalised for offside, Biggar stepped up in the 25th minute to make it 10-0.

Out of nowhere, the visitors then got back into it. Biggar kicked ahead and Reinach chased, but when Saracens regained the ball, Spencer spotted there was no one behind the Saints' defensive line. His box kick went 65 metres, Lewington winning the foot race and flopping over the line for a score Spencer was unable to convert.

It spurred Saracens into life and Lewington was soon over for his second. Brad Barritt crashed the ball up and deft hands from Goode and Liam Williams sent the wing over for an easy finish.

Spencer again missed the kick as the teams went in level.

The hulking Naiyaravoro and Vunipola had provided an earth-shattering collision before the break, James Haskell also stopping a third Saracens try with a neat turnover.

Spencer might have had a poor start with the boot, but he made up for it when the game began by producing a sublime dummy close to the line and dived over.

This time Spencer kicked the conversion and then added a penalty.

Saints attempted a response when Biggar kicked to the corner and a series of home driving line-outs eventually came up trumps.

Saracens were living on the edge and after Vunipola was sin-binned for entering the maul from the side, a fifth set-piece ended with Hartley rumbling over. Biggar kicked the goal.

Goode took over kicking duties and responded with a penalty, but Saints made the most of their man advantage. Replacement Harry Mallinder sprayed the ball to the right wing and when the ball was recycled back left, his fellow substitute Franks powered over.

Biggar converted and then followed Goode by kicking a penalty, but Strettle's late salvo in the final 10 minutes won Saracens the game.

First Goode and Williams combined to send Strettle to the line for the decisive score.

The wing then finished off another Williams break after he claimed a high ball, the first of which was converted by Goode.