Mils Muliaina returns to the fray and will start at full back, while last week's opening try scorer Tiernan O'Halloran shifts to the right wing.
23-year-old Mick Kearney is promoted to the starting lineup and joins Aly Muldowney in the second row while George Naoupu at Number 8 represents the other change to the pack.
Darragh Leader returns from injury to take his place on the bench and his fellow Galway-born team mate Andrew Browne is included amongst the replacement forwards.
Commenting on the team selection and the upcoming game, head coach Pat Lam said:
"With another physical challenge away from home, it's great to be able to bring in fresh legs up front with Mick (Kearney), George (Naoupu) and Andrew (Browne) in addition to the leadership and experience from Mils (Muliaina) out the back.
"Like every game from now until the end of the season, four points against Cardiff is massively important in the context of our ultimate goal.
"Challenges we face this week such as a short five-day turnaround, long travel, and 4G pitch were all identified early on and we tailored our preparation accordingly.
"We know how dangerous Cardiff can be, especially at home. They had a fantastic win against Edinburgh last weekend, playing more of an expansive game and stretching the defence to score some quality tries. Once again, we will need to perform as a team to secure the desired outcome that will leave us in a strong position before the break."
Connacht team to face Cardiff
15. Mils Muliaina
14. Tiernan O'Halloran
13. Danie Poolman
12. Dave McSharry
11. Matt Healy
10. Craig Ronaldson
9. John Cooney
1. Denis Buckley
2. Tom McCartney
3. Rodney Ah You
4. Mick Kearney
5. Aly Muldowney
6. John Muldoon (captain)
7. Jake Heenan
8. George Naoupu
Replacements:
16. Shane Delahunt
17. Ronan Loughney
18. Finlay Bealham
19. Andrew Browne
20. Eoghan Masterson
21. Ian Porter
22. Jack Carty
23. Darragh Leader
Unavailable/Injured: Jason Harris-Wright, Sean Henry, Nathan White, Michael Swift, Willie Faloon, Eoin McKeon, Kieran Marmion, Bundee Aki, Robbie Henshaw, Niyi Adeolokun.
Connacht v Cardiff Blues
At BT Sport Cardiff Arms Park, 7.35pm
Live on BBC Wales/ TG4
Referee: Lloyd Linton (SRU, 7th competition game)
Assistant Referees: Leighton Hodges, Craig Evans (both WRU)
Citing Commissioner: Aurwel Morgan (WRU)
TMO: Gareth Simmonds (WRU)
Guinness PRO12
Suite 208, Alexandra House,
The Sweepstakes
Ballsbridge, Dublin 4, Ireland