Reflecting on the 16-9 reversal against the Scarlets, head coach Matt Williams said: "We were disappointed with our first half. We know we missed tackles we shouldn't have. Our second half performance was much better and we did well to keep the Scarlets to a low score.
"The players understand that their first half performance made it hard for them to get a result but I felt that they finished well in the second half and showed spirit and we took a lot of positives away from the second half."
Asked about this weekend's opposition, he added: "The Blues are an extremely good team. They play a high quality style of rugby and had a good season last year finishing second in the Magners League. Their squad has so much depth."
The Ulster starting line-up and replacements will be confirmed on Thursday morning.
ULSTER Squad (v Cardiff Blues): Backs (11) - Isaac Boss, Paddy Wallace, Timoci Nagusa, Rob Dewey, Darren Cave, Andrew Trimble, Clinton Schifcofske, Cillian Willis, Niall O'Connor, Bryn Cunningham, Ian Humphreys.
Forwards (14) - Justin Fitzpatrick, Nigel Brady, Tom Court, Rory Best, BJ Botha, Carlo Del Fava, Ed O'Donoghue, Ryan Caldwell, David Pollock, Matt McCullough, Kieron Dawson, Robbie Diack, Bryan Young, Thomas Anderson.