"Winning the Heineken Cup was the highlight of my career so far," Thomas said. "Winning my first cap for Wales was massive but to be part of the first side from outside France to win the tournament was a great honour. I have seen a few of Cardiff's game this season and they have the potential to be an exciting team. They will be confident coming up against us, especially at home so we have to be ready for the challenge.
"They haven't been playing as well as they would have liked so far this season but they have a similar squad from last season and are building a real continunity within the group at the moment."
Thomas was an ever-present for the Blues in the Heineken Cup in his two seasons at the Arms Park and he believes the experience the Blues gained from last year's tournament will stand them in good stead this year.
"In the Heineken Cup last year we only won one game but we ran all of the opposition close. They will be hoping to have an extra edge this year given that experience. When they do come together they will be an exciting team and a tough one for us to beat."