Paris - Four-time winners Leinster produced a stunning seven-try, 50-21 victory against Northampton in Dublin on Saturday to become the first team ever to qualify for the quarter-finals of the European Champions Cup after just four rounds.

Ireland centre Gary Ringrose scored a hat-trick of tries as the home side blew away the team they beat in the 2011 final.

They moved to 19 points at the top of Pool 1, enough to guarantee them a place in the knockout rounds with two group games still to play.

Toulouse also moved to within a heartbeat of the last eight with a 26-18 win at Montpellier while defending champions Saracens kept their hopes alive with a hard-fought 15-6 win at home to Munster.

La Rochelle picked up their first win of the tournament in Glasgow, Connacht came from behind to beat Gloucester and Treviso chalked up their first win in the competition since 2015 when they beat French Top 14 leaders Lyon.

Leinster, who won 43-16 in Northampton a week ago, ripped into the Saints from the first whistle, Ringrose charging down a clearance and going through for his first try in just the second minute.

When he added a second four minutes later, Northampton knew they were in for a long afternoon, further tries Tadhg Furlong and Dave Kearney securing the bonus point before half-time.

Northampton battled hard but second half tries from James Lowe, Ringrose and Caelan Doris completed the rout and sent Leinster through to the last eight.

Northampton stay second in Pool 1 on nine points, two ahead of Lyon who slipped to a 25-22 defeat at Treviso where Marco Lazzaroni's converted try eight minutes from time snatched the win for the Italians.

Toulouse all but booked their place in the quarter-finals with a 26-18 win at Montpellier.

A last minute try from Lucas Tauzin, a 71st minute replacement for South African World Cup winning winger Cheslin Kolbe who picked up a rib injury, secured the bonus point for Toulouse who head Pool 5 with 18 points.

They are nine points clear of Gloucester who lost in a dramatic finale to Connacht in Galway.

France flyhalf Romain Ntamack scored Toulouse's first try and they led 14-13 at the break with Montpellier compromised by a serious knee injury to former France number eight Louis Picamoles after just two minutes.

Australian lock Rory Arnold touched down twice in the second half before Tauzin's score in the right hand corner closed the contest.

Montpellier, who scored a try in each half, can no longer qualify.

The other game in Pool 5 brought a dramatic finish as Connacht scored twice in the last four minutes to dent Gloucester's hopes of keeping Toulouse in their sights.

The English side led 24-13 in the 76th minute but with Lewis Ludlow in the sin-bin, Connacht delighted the home crowd with converted tries from Shane Delahunt and Robin Copeland.

Both sides remain in the hunt for a place in the knockout stage.

Champions Saracens scored twice late as they outmuscled Munster in north London and kept their defence alive in Pool 4.

Trailing 6-3 after 65 minutes, Saracens took the lead when Scottish international wing Sean Maitland slithered in down the right.

England prop Mako Vunipola sealed the win when he crashed over from close range.

Munster stay second in the pool with 11 points, six behind French side Racing. Saracens are a further point back in third.

On a wet night in Scotland, Jules Favre and Levani Botia both scored in La Rochelle's win against Glasgow.

The Warriors had number eight Matthew Fagerson sent off for leading with his forearm in the build-up to a try that was subsequently disallowed and now face a tough route to the last eight.