It's an all-southern hemisphere affair in the semi-finals of the 2015 Rugby World Cup, with New Zealand, South Africa, Australia and Argentina all sealing a place in the last four, with some doing so with more drama than others. Here's our quick look at what to expect now the tournament has reached the semi final stage. 

New Zealand v South Africa

All Blacks coach Steve Hansen has already upped the ante for Saturday's game at Twickenham, describing their contest with South Africa as being 'like playing your brother or your sister and you don't want to lose, particularly if you're the younger sibling".

South Africa will have been well aware of New Zealand's capabilities before the humiliation of France, having mustered just one win in their last seven meetings with their Rugby Championship rivals.

Yet if the Springboks can show the same power in the back row that eased them past Wales, they will certainly be in with a chance of overturning the odds.

Australia v Argentina

Sunday's semi final sees Argentina take on the Wallabies, the latter having put in some superb performances so far. The fantastic win over England in the Pool stages shows Australia are capable of producing a level of flair that can harm even the best teams.

However, gritty wins over Wales and Scotland have shown the Aussies can grind out results if needed.

Having secured an impressive win over Six Nations champions Ireland in the quarter finals, Argentina have already proven to be a team that cannot be underestimated.

History is not on the side of the Pumas, however, having secured one win in their 11 meetings with the Wallabies. A solid scrum and the boot of Nicolas Sanchez are likely to be instrumental in any success this time around.