It will be the first time the pair have come up against each other in a competitive match despite battling for starting places for Wales, and coming through the Welsh international set-up together. In what will be an enthralling encounter across the board, with the Ospreys fighting for a place in the Rabo Direct PRO12 play-offs, that one on one tussle will excite all rugby supporters and observers alike, not least the Lions selectors ahead of Warren Gatland's squad announcement for the tour to Australia.
Warburton said, "I think I've only played against the Ospreys twice, most recently at home at the Cardiff City Stadium on New Year's Eve 2010 where we narrowly won 27-25 with Marty Holah in the Ospreys side. That was a good memory but the year before, we played away on New Year's Day 2010 and lost 26-0 so that was a bad one. It's a mixed bag but I'm really looking forward to this one.
"I've never played against Justin Tipuric before, seven on seven. It's a battle I'm really looking forward to, especially in the contact area. It's well publicised how important that area is in the modern game so whoever comes out on top in that area will have an advantage. It will be an interesting one."
The Blues flanker reckons the Ospreys will provide a threat throughout the side but especially in the forwards. "I think the Ospreys will go for us up front. Their whole pack is a threat and I couldn't single out one player. I've been really impressed with them this season. They seem to have great unity whoever plays and so they'll be a huge challenge.
"Bradley Davies will be a big miss for us, especially against the Ospreys, as that game would have suited him down to the ground. Lloyd Williams will be important, he's an immense player. He doesn't get as much publicity as some but he's very good at keeping the tempo going which is how the Blues want to play. A hard pitch should allow him to flourish.
"He's an old school nine with a great pass, a great dummy and great pace. He's immensely fit, reads the game well and knows when to kick. He can surprise a few people - when he gets given a chance he always impresses."
Warburton is relishing the chance to get back onto the Millennium Stadium pitch, and this time in his regional colours. "I haven't played a regional game at the Millennium Stadium before - some of the players have played Heineken Cup knock-out games there. I'm very proud to play for the Blues and it will be really exciting to play here. I'm sure it will be a match no player will have to get motivated for, especially for us. We can't make the latter stages so this is one game everyone wants to be involved with."
Warburton's Wales back row team mate and opposite number Justin Tipuric is also looking forward to Judgement Day. "I've played twice against the Blues. In one game, we were down to six men in the scrum against them in the LV= Cup and we were on our own line. Everyone thought the Blues would get a push over try but our front five managed to push them off the ball, so that's something that stands out. They're physical derby games and ones everyone wants to win."
Tipuric is taking nothing for granted as the Wales players return to their regions after the RBS 6 Nations. "Sam Warburton and I have done ok in the same team but we have to go back and win our places in the regional sides now. As a team, we will have to be disciplined as the Blues have got a great kicker in Halfpenny, and Cuthy and Leigh can finish the scores. But it's going to be a physical game and we need to be aware of their pack.
"You can't give away too many penalties in a derby game like this. That's going to be crucial. It's about the team more than anything and the 15 players on the pitch. Hopefully we will play well as a team and if we do that then we can hopefully get the win.
"We've got a game with the Dragons on Friday night and then obviously the big one on Judgement Day so hopefully we'll build some momentum going into that. I think it will be exciting and we can play some open, running rugby in front of a good crowd back at the Millennium Stadium."
Judgement Day - Millennium Stadium, Saturday 30 March
Dragons v Scarlets 2.30pm
Blues v Ospreys 5.15pm
Tickets: Adults £25, U18s £10, Family ticket £50 (two adults, two children)
Tickets available from wru.co.uk/tickets; by calling Ticketmaster on 08442 777 888; from Ticketline, Westgate Street Cardiff tel 02920 230130; from the Blues and Dragons box offices; from the WRU store, 47 Westgate Street, Cardiff, and from selected Tesco stores around Wales.