Danny Wilson’s side have already secured a place in the end-of-season European Champions Cup qualification play-off, but will be keen to seek revenge following the 46-24 defeat at the hands of Tandy’s men at the Liberty Stadium earlier in the season.
Four changes have been made from last week’s 24-24 draw against Ulster, with Matthew Morgan, Nick Williams and Macauley Cook replacing the injured Blaine Scully, Sam Warburton and George Earle.
Kristian Dacey also comes into the starting line-up and is named at hooker, replacing Matthew Rees who drops to the bench.
Rey Lee-Lo and Willis Halaholo continue their partnership in the centre, following their devastating performance in Belfast last week, while Alex Cuthbert and Rhun Williams partner Morgan in the back three.
Ellis Jenkins starts at openside with Josh Navidi, who has scored in two consecutive Judgement Day fixtures, named at blindside. Gethin Jenkins captains the side.
Meanwhile, Ospreys will be looking for a response, following back-to-back home defeats to Stade Francais and Leinster, in order to keep their Guinness PRO12 semi-final hopes alive.
Sam Davies is handed the number 10 jersey, after Dan Biggar was ruled out with concussion, with captain Rhys Webb starting at scrum half.
Back row Sam Underhill is absent, after also suffering a concussion during last week’s defeat to Leinster, which sees James King, Justin Tipuric and Dan Baker starting in the back row.
What They Said
Josh Navidi is relishing the unique atmosphere of Judgement Day as Cardiff Blues prepare to face the Ospreys in front of more than 50,000 at the Principality Stadium on Saturday.
Navidi said: "It's becoming a big occasion now. Each year they're selling more and more tickets from when it started five years ago - they've already sold fifty or sixty thousand tickets.
"It's good for Welsh supporters to have both games on and good for us to have a full-ish stadium to play under - the atmosphere is amazing, just running out onto the Principality Stadium.
With so many internationals on show and going head-to-head in the respective matches, Navidi admits it is a chance to impress national selectors.
The 26-year-old has been unfortunate not to add to the Wales cap he won in the summer of 2013 but he hopes to stake a claim for another.
He continued: "I haven't thought of it like that to be honest it's a big occasion and each year you want to put a good performance and big shift in and hopefully we can play well and cross that whitewash again.
"Four years ago is a long time ago. Obviously I'm always itching to get another cap so hopefully I can go on the tour and add something, maybe I can get another cap or two."
Meanwhile, Gareth Anscombe has called on Cardiff Blues to physically front-up to the challenge of the Ospreys on Judgement Day.
"We've been buoyed by our last few performances, a couple of tough losses and a draw but our performances have been in the right direction.
"If you look at our last four games we've probably played the toughest teams in the competition. We should've beaten Leinster but we blew a few chances and we were winning in Ulster away with a few minutes to go.
"We're obviously doing enough to compete with these top teams but it seems we're not ruthless enough at times, probably without the ball and we'll try and rectify that because that's what's hurting us.
"The results can get you down but we try just to worry about performance and I think looking back at the past month or so we've certainly improved.
"The Ospreys taught us a few lessons earlier this season, we went there full of confidence and left with our tails between our legs.
"We didn't front up and we've found that in these derbies if you don't physically front up you have a tough day at the office.
"We need to have the right attitude to front up and get stuck in and hopefully we have a chance in the last twenty minutes and see what happens."
Cardiff Blues will be hosting a pre-match fanzone at BT Sport Cardiff Arms Park, between 12pm - 2.15pm, which will include a regional choir off, street food and an exclusive Q&A session with Sam Warburton. More information here