Harlequins plundered six tries to win a pulsating game against Premiership leaders Northampton Saints at Twickenham.

Luke Northmore and Will Porter both scored twice as the home side lost three players – Danny Care, Louis Lynagh and Tyrone Green – to the sin-bin.

Care avoided a red card in the second half as Quins claimed a win that bolstered their play-off hopes with two games left.

They are level on points with fourth-placed Bristol, with a trip to Exeter and a potentially decisive home game against the Bears to conclude the regular season.

Harlequins led inside two minutes after Marcus Smith’s pinpoint, cross-field kick found Northmore in space on the right wing to dot down in his first start in six months.

Quins lost Care to the sin-bin seven minutes in after a collision of heads between the scrum-half and his former England team-mate Courtney Lawes, but Saints failed to capitalise when they had the extra player.

Northampton got on the board midway through the first half as the league’s top scorer Ollie Sleightholme latched on to Tom Litchfield’s kick, with a hint of a forward pass in the build-up.

Fin Smith converted and then landed a penalty soon after to take Saints into double figures.

Northmore darted through to score his second try right behind the posts, with Marcus Smith converting to retake the lead for Quins.

Lynagh was then shown a yellow card for knocking down a pass in front of his own line and Fin Smith opted to kick the penalty for a one-point lead as Quins were again reduced to 14 players.

But the Londoners kicked on despite the deficit and worked the ball up to the tryline, with captain Stephan Lewies eventually able to find a way through the wall of Northampton defenders for the try.

Sam Graham’s score for Saints right before half-time was disallowed for a controversial knock-on to give the hosts a six-point lead at the break.

Quick passing between Care and Smith set up Cadan Murley to run in his third try of the season and secure the bonus point for Quins early in the second half before James Ramm swiftly hit back for Saints with the game’s sixth try.

Harlequins were reduced to 14 for a third time when Green was sent to the bin for a deliberate knock-on.

And Care avoided a second yellow card after he appeared to dive over the top at the ruck to steal the ball, with the scrum-half looking relieved as he was immediately replaced by Porter.

Litchfield scored to put Saints back in front with less than 20 minutes to go.

But two tries from Porter opened up a cushion for Harlequins as the clock ticked down, with replacement Jarrod Evans clinching victory with a penalty after Lawes scored Saints’ fourth try to give the leaders a losing bonus point.

They are four points clear of second-placed Saracens with remaining league games against Gloucester (home) and Bath (away) after next Saturday’s European Champions Cup semi-final against Leinster in Dublin.