Sydney - The Sharks will be out to extend their Super Rugby lead this weekend against the Lions, while the Brumbies aim to stay top of the Australian conference.
Jake White's Sharks are on top of both the South African conference and the overall standings with 23 points from six games.
The Durban-based outfit are coming off a bye and travel to Johannesburg where they have only lost three times in 10 encounters with the Lions.
"We've had a break now and that was very good for us as a team, getting away from things," flanker Marcell Coetzee said.
"We're back now and have to pick up where we left off in the last game and give everything."
Lions captain Warren Whiteley said his team need to hit back quickly after an ignominious last start 28-7 loss at home to the Crusaders.
"The Sharks will be our last home game before we tour (Australasia), so we need to stand up and be counted," Whiteley said.
"We're still a young group and the guys would have learnt from this experience, but we need to pick ourselves up and produce a big performance this weekend."
Wallabies frontrowers Stephen Moore and Scott Sio return to bolster the Brumbies against the Reds in Brisbane on Friday.
The Brumbies lead the Australian conference by just one point from the Waratahs, but have an impressive record at Brisbane's Suncorp Stadium.
Stephen Larkham's Brumbies have won seven of their 10 games in Brisbane and lead the Reds 17-5 overall with one draw.
The Reds downed the Brumbies 27-17 in their opening game in Canberra, but flyhalf Matt Toomua says his team have improved.
"The Reds were very sharp (in round one) in the effort areas, they were desperate in that game," Toomua said.
"They looked complete, but we've improved since then. We're in a better place now than we were in round one."
The Reds have recalled centre Anthony Faingaa and Chris Feauai-Sautia to their injury-hit backline as the Reds look to improve on losing three of their last four matches to be in 11th place.
Coach Richard Graham said the Reds needed to be better at closing out games after failing to put the Lions and Western Force away in costly losses.
"We have lost two of our last three matches by three points, so controlling the back end of the game will be important," he said.
Back-to-back champions Chiefs will be looking to Gareth Anscombe to slot seamlessly into the fly-half spot after Aaron Cruden was ruled out for six weeks with a broken thumb in Saturday's home match with the Melbourne Rebels.
"It's a chance for me to have a go in that spot and it's one I've been looking forward to," Anscombe said.
"Cruds has been pretty indestructible for this team the last few years, so I guess it's an opportunity now to get a few games at 10 and it's one I'm really excited about."
The Chiefs have a four-point buffer over the Wellington Hurricanes in the New Zealand conference.
The Waratahs face an in-form Force, chasing their fifth straight win in Perth on Saturday.
The fourth-placed Waratahs can open up a potentially decisive break on the fifth-placed Force or surrender their spot in Australia's top two to the Perth-based outfit.
"It's an important game in the bigger picture of the comp, that's for sure," coach Michael Cheika said.
"It's an away game and they have been so hard to win - across the board for any team - so if we can take a home game off one of our conference challengers, then it puts you in a good position."
Waratahs fullback Israel Folau will make his return in the game after being sidelined for two weeks with a throat injury.
In the remaining games, the Highlanders host the Bulls and the Cheetahs are at home to the Crusaders, while the Blues, Stormers and Hurricanes all have a bye.