**Cardiff Blues and Edinburgh face a must-win fixture when they meet at the Arms Park on Monday night.**\n\nBoth sides are bidding to chase down the third-placed Scarlets, who are in action against Connacht at the same time in Llanelli. \n\nWith third expected to be enough to secure Heineken Champions Cup rugby and uncertainty surrounding any further allocated spots, the success of the teams’ campaigns could be riding on whether they achieve a top-three finish. \n\nHere, we take a look at how things stand in Conference B and what could unfold on Monday night. \n\n**How it stands** \n\nFollowing last weekend’s results, the Blues trail third-placed Scarlets by three points having played the same amount of games as their fellow Welsh region. \n\nEdinburgh, meanwhile, are a further seven points back but remain in the hunt for third thanks to their dramatic late victory over Connacht last weekend and their two games in hand over both their rivals.