Wales’ Capital Region are battling to reach the top three in Conference A and need to prevail over the Irish province to remain in the play-off hunt.
Head coach John Mulvihill has made three changes to the side that slipped to defeat against Munster last weekend, while reshuffling his pack for the return trip to Ireland.
Jason Harries is restored to the starting line-up in the place of Aled Summerhill in the only change among the backs. Up front, Ethan Lewis replaces Kristian Dacey, who is ruled out through injury, and George Earle comes in for Shane Lewis-Hughes.
That sees Seb Davies pulling on the number eight jersey, after Nick Williams failed to return from injury, and Josh Turnbull moves across to blind-side flank.
Mulvihill said: “Gareth’s fully fit and running the show at the moment. He hasn’t played out in Connacht during his four seasons here, and he’s leading us, so he’s looking forward to that. We have a lot of other leaders in the group, so it doesn’t just come down to him.
“We gave Kristian (Dacey) and Nick (Williams) as much time as possible but they haven’t quite come through. Ethan comes in for Dacey, and he’s been going well, and Seb goes into the back-row so we’re still in good shape.”
The Blues are currently four points behind Connacht, who sit third, and must triumph at the Galway Sportsground to keep alive their hopes of a PRO14 play-off.
They then face the Ospreys at the Principality Stadium on Judgement Day (April 27), which is increasingly living up to its billing.
Mulvihill is under no illusions of the importance of the fixture and knows Connacht will present a formidable challenge but he has been pleased with his team’s progress.
He said: “This is a grand final for us and if we don’t get the result that we want we will be looking to a fourth-placed play-off. The club has never played in the final series so that’s our burning desire.
“The boys have approached this game and trained during the week as if it is a final. It’s knockout competition now and we are looking forward to the challenge.
“Connacht are a quality outfit, who have come into a bit of form, and we have known for some time it would come down to this game and Judgement Day. It is great for the competition and we are determined to stay in the fight by winning in Connacht.”
Cardiff Blues: Matthew Morgan; Owen Lane, Rey Lee-Lo, Willis Halaholo, Jason Harries; Gareth Anscombe (capt.), Tomos Williams; Rhys Gill, Ethan Lewis, Dillon Lewis, George Earle, Rory Thornton, Josh Turnbull, Olly Robinson, Seb Davies
Replacements: Liam Belcher, Rhys Carre, Dmitri Arhip, Shane Lewis-Hughes, James Botham, Lloyd Williams, Jarrod Evans, Garyn Smith