With dual leaders Rob Herring and Andrew Trimble returning from injury and named on the bench, Best gets the opportunity to steer Ulster past a difficult hurdle in which defeat could halt their drive for a top four finish.
Best is the only new face in the front five, while with Chris Henry sidelined, Roger Wilson comes in at number eight with Sean Reidy at open-side. Behind the scrum, Paddy Jackson is the only change in personal to a potent back-line, with Stuart Olding partnering Luke Marshall in the midfield.
With grounds hardening up, Ireland star Iain Henderson, who has just returned from honeymoon, again starts at blindside. With fourth-paced Ulster having Munster (2nd, away), Ospreys (3rd, away) and Leinster (1st, home) in a tough end of season run-in, Henderson knows a win tonight is crucial.
“It’s a fun and interesting part of the season. The weather is starting to perk up a bit, and we should expect to see some good performances,” said Henderson. “It is definitely crunch time for us.
“If we lose to Cardiff, that would be the most difficult defeat to take though. Obviously, Munster are playing phenomenal rugby and are doing really well, as they’ve done for the majority of the season. Leinster and Ospreys as well.
“It’ll be interesting, but that’s what makes good rugby and that’s why we enjoy playing rugby. We’re definitely aiming to finish as high up the table as we can and want to be pushing for the top two.”
Cardiff, meanwhile, have made four changes to their side with former Ravenhill favourite Nick Williams named on the bench.
J Payne; C Gilroy, L Marshall, S Olding, C Piutau; P Jackson, R Pienaar; A Warwick, R Best (capt), W Herbst, K Treadwell, A O’Connor, I Henderson, S Reidy, R Wilson.
R Herring, C Black, R Ah You, R Diack, N Timoney, P Marshall, J Stockdale, A Trimble.
R Williams; A Cuthbert, R Lee-Lo, W Halaholo, B Scully; G Anscombe, L Williams; G Jenkins, M Rees, T Filise, G Earle, J Hoeata, E Jenkins, S Warburton, J Navidi.
K Myhill, C Domachowski, K Assiratti, J Down, N Williams, T Williams, S Shingler, M Morgan.