The 1999 champions, who face Stade Toulousain in the Round of 16 next month, overcame reigning United Rugby Championship winners Leinster 18-13 in Belfast in the battle between the top two teams in the league.

First-half tries from Sam Carter and Michael Lowry set up the victory, with Nathan Doak kicking a conversion and penalty.

All but three points were scored before the break, when Max Deegan crossed for Leinster’s sole try converted by Ross Byrne, who also kicked a penalty. Byrne’s second penalty sealed a losing bonus point which kept Leinster top prior to their last-16 meeting with Connacht Rugby.

Leicester Tigers, who take on ASM Clermont Auvergne in the last 16 of the Heineken Champions Cup, are still top of the Gallagher Premiership too, after cruising to a 47-28 home win over London Irish.

Steve Borthwick's side ran in seven tries, comprising two for Nemani Nadolo and one apiece for European Cup record try-scorer Chris Ashton, Matt Scott, Harry Potter and Tommy Reffell, plus a penalty try. Freddie Burns converted five.

Harlequins remain in third after coming from behind to triumph 38-29 at Bristol Bears in a 10-try thriller between two more last 16 Heineken Champions Cup teams.

Quins, who meet Montpellier Hérault Rugby next month, notched six tries via Cadan Murley (2), Tom Lawday, Hugh Tizard, Jack Walker and Luke Northmore, while Bristol’s quartet came from Steven Luatua, Sam Jeffries, Dave Attwood and Bryan Byrne.

Sale Sharks, who face Bristol in the Round of 16, pipped Gloucester Rugby 26-24 at the AJ Bell Stadium, with Faf de Klerk, AJ MacGinty, JP du Preez and JL du Preez scoring tries, three of which De Klerk converted.

However, 2020 champions Exeter Chiefs, who take on Munster Rugby next month, lost 35-31 at Worcester Warriors, where Santiago Grondona, Tom O'Flaherty, Jack Innard, Max Norey and Dave Ewers touched down for the visitors.

Munster were also beaten on Saturday, succumbing 29-24 at Blue Bulls in the URC despite scoring more tries than their South African hosts, who conceded efforts from Alex Kendellen, Damian de Allende and Jack O'Donoghue.

Ulster Rugby underlined their Heineken Champions Cup credentials on Saturday by completing a domestic double over four-time European champions Leinster Rugby for the first time since 2013.