Fly-half Gordon Ross kicked 23 points as Saracens kept their hopes of an EDF Energy Cup semi-final place alive with victory over Northampton.

But they will need to win their final Pool D match at Bristol next Saturday and rely on Northampton beating group leaders Scarlets for the outcome to be decided on bonus points.

Ross kicked six penalties, a conversion and a drop goal while opposite number Stephen Myler kicked three penalties.

Both sides scored two tries, with England Under-20 left-wing Noah Cato and scrum-half Moses Rauluni striking for Saracens and full-back Ben Foden and number eight Roger Wilson replying for the visitors.

Cato scored in the 11th minute when his pace took him past scrum-half Lee Dickson and his power enabled him to run through Foden's challenge and over the line.

Northampton retaliated with two penalties from Myler to one by Ross before Cato was sin-binned in the 20th minute.

Chasing the kick-off following Myler's second penalty, he took out Matt Lord while the Saints lock was still in the air and referee Martin Fox had no hesitation brandishing the yellow card.

Sarries ignored the handicap to increase their lead to 15-6 when Rauluni snatched the ball from the base of a ruck and ran straight between the posts to leave Ross an easy conversion.

But Northampton hit back to conjure up two tries down the right wing.

Myler made the initial break for the first, releasing Chris Ashton to race clear and pass inside for Foden to touch down.

Ross nosed Saracens further ahead with his second penalty before Myler's soaring kick to the right wing was collected by Wilson, who spun out of Andy Saull's touchline tackle before crossing in the corner.

Saracens, grateful to see Cato return, restored their five-point lead when Ross calmly dropped a goal with the final kick of the first half.

Ross squandered a simple penalty chance a minute into the second half but made amends by landing one from 40 metres seven minutes later.

Left-wing Paul Diggin was Northampton's main threat and the pressure paid off when Northampton forced a 55th-minute penalty to close the gap to five points.

But they were denied a losing bonus point when Ross kicked two more penalties in the 61st and 68th minutes.

Northampton produced big guns Carlos Spencer, Scott Gray and England elite squad hooker Dylan Hartley from the bench in a bid to salvage something from the game but, two minutes after replacing Shields, Hartley was fortunate to stay on the field when he escaped with a warning for a high tackle on Rauluni.

The visitors continued to press in the final stages but some desperate defending by Saracens kept them out before Ross struck the final blow, landing his sixth penalty with the final kick of the game.