Cardiff's Principality Premiership fixture against Glamorgan Wanderers at Cardiff Arms Park on Saturday (21 October) will kick-off at 1.30 pm.
Blue & Blacks' team manager Keith Morgan said, "This week's match is a very attractive local derby but we are aware that many supporters from both clubs would like to see the game live at the Arms Park and also have a chance to watch Cardiff Blues play their opening Heineken Cup match in Bourgoin on television.
"We are playing some good rugby at the moment and our support is growing so it seems only sensible to accommodate both matches. Let's hope we can have a big crowd at the Arms Park for the earlier kick-off and then everyone is welcome in the clubhouse to watch the regional side on television at 3.30pm."
Saturday's match will also be Cardiff's one-hundredth Premiership fixture since Welsh club rugby was reorganised in September 2003.