A youthful Leinster team maintained their BKT United Rugby Championship table-topping form with a 38-14 win over Cardiff at the RDS.
Cardiff inflicted a first defeat of the United Rugby Championship season on defending champions the Stormers with a thrilling 30-24 win in Wales.
A brace of tries from Johnny McNicholl along with scores from Sam Costelow and Sione Kalamafoni, who was later red-carded, earned the Scarlets victory. Josh Adams and James Botham scored Cardiff’s tries.
Theo Cabango scored two tries as Cardiff produced a second-half URC comeback to stun high-flying Glasgow at the Arms Park.
Rhys Priestland steered Cardiff to a hard-fought 23-17 victory as his side survived a second-half onslaught from the Sharks.
Jarrod Evans kicked a late penalty to secure Cardiff Blues a third victory this season over the Scarlets, winning 29-28 in Llanelli.
Cardiff’s Owen Lane and Dragons’ Rhys Lawrence were both shown red cards for high challenges as the Blues edged their PRO 14 Rainbow Cup clash 17-16.
Cardiff Blues staged a remarkable second-half comeback to beat Benetton 34-24 and keep their Pro 14 play-off hopes alive.
Ulster cantered into an early 17-point lead in Belfast but they then lost their way against Cardiff and their winning performance ultimately left much to be desired.