The likes of Connacht and Edinburgh are looking to secure their berths in the knockout stages with a round to spare.
Meanwhile, Zebre and the Dragons can build momentum for the second half of the season and Cardiff Blues face an historic clash on home soil.
Edinburgh Rugby v Stade Francais
Venue: BT Murrayfield
So far, so good for Richard Cockerill and Edinburgh in Europe this season.
The Scottish side have won 13 of their last 14 home fixtures in the Challenge Cup, with their only defeat in that run coming in last season’s quarter-final against La Rochelle.
FULL STORY | Sutherland returns as Edinburgh look to secure a home quarter-final in the @ERChallengeCup.
— Edinburgh Rugby (@EdinburghRugby) January 11, 2018
They are the top points (238) and try (35) scorers in the Challenge Cup after four rounds.
They have a maximum 20 points from 20 and if they manage to defeat Stade Francais at BT Murrayfield on Friday evening, they will win Pool Four and secure a home quarter-final.
Stade – the defending champions – are currently eight points behind Pool Four leaders Edinburgh but racked up back-to-back victories in their last two Challenge Cup games, beating Krasny Yar 39-24 before edging out London Irish 26-20 at the Madejski Stadium.
Worcester Warriors v Connacht
Venue: Sixways Stadium
If Connacht happen to come away from Worcester Warriors on Saturday with a victory, the Irish province will win Pool Five and book their spot in the knockout stage for the ninth time.
If selected, captain John Muldoon will make his 50th Challenge Cup appearance but it is his teammate Jack Carty who has been key to their impressive four wins from four so far.
Squad Spirit. European focus this week ahead of two crucial clashes in @ERChallengeCup Pool 5.
— Connacht Rugby (@connachtrugby) January 10, 2018
The fly-half is the competition’s leading scorer with 53 points after four rounds.
The clubs have met five times previously, with Worcester winning the first meeting back in 2005-06 – however, Connacht have won all four games since then.
Pau v Zebre
Kick-off: 6pm (local time)
Venue: Stade du Hameau
Michael Bradley’s Zebre have only won one of their three trips to France in European competition to date and come up against a Pau side full of confidence.
Zebre won on their first trip to France – against Brive in 2014-15 – however, they have lost all three matches away to TOP 14 opposition since then.
— Zebre Rugby (@ZebreRugby) January 11, 2018
The Italians have averaged 14.8 penalties conceded per game so far, more than any other side.
They came close in Parma in the reverse fixture but the Top 14 side ran out 38-33 victors.
Bordeaux-Bègles v Dragons
Kick-off: 9pm (local time)
Venue: Stade Chaban-Delmas
Bernard Jackman’s Dragons have won six of their last eight pool games against TOP 14 opposition, losing twice, although both defeats in that run came in France.
The clubs have met twice previously, both encounters coming during the 2013-14 pool stage, with the home side on the day winning each match.
The kicking of Angus O’Brien could be key for Jackman – the Welshman has laid on four tries with his kicking from hand and will be hoping for more this weekend.
READ | “We like to be underdogs” – Dorian Jones is looking forward to the challenge of taking on Bordeaux this weekend #ERChallengeCup
— Dragons Rugby (@dragonsrugby) January 11, 2018
Bordeaux-Bègles have lost just one of their six previous games against Welsh opposition in the Challenge Cup while their biggest victory in the competition came at home to Ebbw Vale in 1996.
Cardiff Blues v Toulouse
Venue: Cardiff Arms Park
The first-ever European final saw Cardiff Blues take on Toulouse, and it is happening again this weekend.
But this time, it is in the Challenge Cup as the Blues aim to hold off Toulouse in their Pool.
A Jarrod Evans conversion helped the Blues down the French side when they met at the Stade Ernest Wallon, Danny Wilson’s emerging 17-15 winners.
— Cardiff Blues (@cardiff_blues) January 11, 2018
This will be the second meeting between the clubs in the Challenge Cup but their tenth encounter in Europe overall.
Cardiff Blues have won on all three occasions when they’ve hosted Toulouse in Europe, all in the European Cup. All three fixtures were won by single figure margins.
Cardiff Blues top their pool despite having scored fewer points (60) than any other side in the Challenge Cup this season after four rounds.
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