The two-sides lie just outside the play-off places, tied on 45-points, making the Cardiff City Stadium showdown crucial to their title hopes.
The Blues included Grand Slam duo Alex Cuthbert, who scored the match-winning try against France, and scrum-half Lloyd Williams.
But the capital city outfit are without Jamie Roberts, Leigh Halfpenny, Gethin Jenkins and Sam Warburton.
“Players from both teams contributed significantly to the Wales team success and we have looked at these returning international players individually to see where they are mentally and physically,” said Blues backs coach Gareth Baber.
“It is important to get them back into our set up and get them comfortable in what we are doing again. Then hopefully they can go out and perform, pushing the potential of the squad.
“Now that we are entering the business end of the season the competition level rises and everybody is fighting for positions in the starting XV.
“That is what you want as a coach; you want people competing and pushing each other hard.”
The Scarlets include six of their Welsh Six Nations stars in their squad including Matthew Rees, Ken Owens, Jon Davies and Scott Williams, while Scotland’s Sean Lamont and England’s Ben Morgan start.
“We know we need to win every contest now in the final run-in for top four places,” said Scarlets head coach Nigel Davies.
“And there can be no bigger games that the two contests we have with the Blues away this weekend and then back with us at Parc y Scarlets on 5 May.
“We are mindful of the intensity of the Six Nations and the players that have been in the national set-up now for the past 10 weeks and we will manage individual players in the best way possible.”
