Last week's win over Toulon means very little unless Clermont win the Top 14, says Sky Sports' Jonathan Davies.
Scarlets came from behind to beat Treviso 17-13 and secure a place in next season's European Champions Cup.
Ken Owens scored the only try of the match as Scarlets won 16-6 in their Guinness Pro12 derby against the Cardiff Blues.
With one round remaining and the top four sides split by a point there is still everything to play for in the PRO12.
Stuart Barnes says that players should not be banned for accidental acts after Iain Henderson was red-carded for Ulster.
The Scarlets host Cardiff Blues on Sunday needing a victory to keep them on track for a top-six finish.
Watch all the highlights of this weekend's Guinness PRO12 action.
The Scarlets moved into sixth spot in the PRO12 after a bonus-point victory over the Dragons at the Millennium Stadium.
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