South Africa's Northern Bulls, refreshed from last week's bye, look set to keep the heat on their Super 14 title chase when they host New Zealand's Otago Highlanders on Saturday.
The Bulls head the southern hemisphere provincial championship standings on points differential from last year's finalists Waikato Chiefs, but crucially have a game in hand on all their main rivals after four rounds.
While the Pretoria-based defending champions are favoured to take the points against the Highlanders, the four teams below them are playing each other.
The Chiefs, who missed an opportunity to be sole tournament leaders when they crashed at home to the Queensland Reds last week, have a tough New Zealand derby with seven-time champions Canterbury Crusaders in Hamilton on Friday.
The third-placed Western Stormers are at home in Cape Town against fourth-placed Wellington Hurricanes on Saturday.
The Coastal Sharks, who were unlucky to go down in a tight one against the NSW Waratahs last week, are up against the sixth-placed ACT Brumbies in Canberra on Saturday, while the Waratahs entertain the Golden Lions on Friday.
The Queensland Reds will have an Australian derby against the Western Force in Brisbane on Sunday, while the Auckland Blues and Cheetahs have the weekend off.
