Blues have lost their last two Guinness PRO12 encounters but have not lost three in a row in the Championship since November 2015.
The Capital side's only defeat to a fellow Welsh region at BT Sport Cardiff Arms Park since December 2013 was to Newport Gwent Dragons in the PRO12 on Boxing Day 2014.
Scarlets have won their last three matches in the Guinness PRO12 but have not won four in a row in the competition since this time last year.
Scarlets only victory in their last five away games in all tournaments was 22-6 in Treviso in the PRO12 round 5.
The west Walians have won three of their last four fixtures against fellow Welsh regions.
The Blues achieved the season's double over Scarlets last year for the first time since season 2009/10.
Scarlets have not been successful on Cardiff soil since a 9-6 victory at BT Sport Cardiff Arms Park in December 2012.
Overall Guinness PRO12 head to head record:
Played 26, Cardiff Blues won 10, Scarlets won 16.
At BT Sport Cardiff Arms Park, 7.35pm. Live on BBC Wales
Referee: Lloyd Linton (SRU, 15th competition game)
Assistant Referees: Cammy Rudkin (SRU), Dai Cambourne (WRU)
Citing Commissioner: John Charles (WRU)
TMO: Neil Paterson (IRFU)
Suite 208, Alexandra House,
Ballsbridge, Dublin 4, Ireland