Dragons, RC Toulon, Bordeaux-Begles and Leicester Tigers all chalked up domestic victories of varying degrees of difficulty at the weekend, with Pool 4’s Bristol Bears the only pacesetters to taste defeat – at Leicester.

Furthermore, with all five front runners facing their nearest challengers next weekend, Scarlets and Edinburgh Rugby warmed up for their respective Pool 2 and 3 encounters against Toulon and Bordeaux-Begles with welcome Guinness PRO14 wins.

Scarlets squeezed home 16-14 at Cardiff Blues, where Leigh Halfpenny was the match-winner with 11 points. In contrast, Toulon overwhelmed Castres 43-3 at Stade Mayol with six tries.

There were also comfortable domestic wins at the weekend for Edinburgh, who romped home 61-13 against South African outfit Isuzu Southern Kings at BT Murrayfield with nine tries and seven Jaco van der Walt conversions, and Bordeaux-Begles, who defeated Bayonne 22-3 at home.

Pool 1 pacesetters Dragons, who travel to Castres Olympique next Saturday, defeated Heineken Champions Cup side Ospreys 25-18 in the Guinness PRO14 on Saturday, when Adam Warren’s late try clinched victory and Sam Davies kicked 10 points.

On the same day, Leicester, who entertain Cardiff in Pool 5 next Sunday, overcame Bristol 31-18 at Welford Road in the Gallagher Premiership, with Jonny May scoring two of the Tigers’ four tries and George Ford contributing 16 points.

A consolation for Bristol as they approach next Saturday’s home game against Brive is that the French club also lost at the weekend, although only narrowly, 29-26 at Montpellier, in the TOP 14.

Four of the five European Rugby Challenge Cup pool leaders will enter next weekend’s potentially decisive Round 5 fixtures in winning form.