Highlanders v Crusaders, Forsyth Barr Stadium, Dunedin

19:35 local, 07:35 GMT, 17:35 EST, 17:05 CST, 15:35 WST

Head to Head: Played 23; Highlanders 8, Crusaders 15

In Dunedin: Played 10; Highlanders 5, Crusaders 5 (* Highlanders 1-0 at Forsyth Barr)

Last clash: Round 10, 2013 - Crusaders 24 - 8 Highlanders, AMI Stadium, Addington, Christchurch

Preview: The Highlanders have a major task ahead of them over the remaining three rounds of Super Rugby; bridging the points gap to the teams immediately above them to avoid the wooden spoon for season 2013. If they want it enough, it's quite achievable, with the Southern Kings currently only two points further ahead (and with three tough derbies coming up), and the Western Force only another three points ahead again.

The Highlanders might have a tough ask this weekend, facing the Crusaders, but after that comes very winnable games against the Hurricanes in Wellington, and the Rebels in Melbourne. If they want it enough, avoiding the spoon is quite achievable.

But if we've learned anything from history, and we should have, given how much they've featured in post-season action, we'll know that the Crusaders are starting to fall back into their groove.

They did enough to get home by a point in their last-start win over the New South Wales Waratahs, and that's the sort of result we should start getting used to for the Crusaders.

All the big guns have been there and done it before. Dan Carter found some form and fitness in the Test series against France, while Kieran Read returned like he'd never been away. And then there's the Richie McCaw factor, with the inspirational All Blacks and Crusaders due for a return any day now.

The Highlanders are capable of pulling off an upset, with the form of Ma'a Nonu and especially Ben Smith only getting better during the June Tests, but they will have to repeat their superb 15-man effort against the Blues in round 16, where they dominated our Team of the Week. It's hard to see the Crusaders folding like the Blues did, though.

Tip: Crusaders by 15

Sharks v Blues, Kings Park Stadium, Durban

14:50 local, 12:50 GMT, 22:50 EST, 22:20 CST, 20:50 WST

Head to Head: Played 16; Sharks 12, Blues 4

In Durban: Played 9; Sharks 7, Blues 2

Last clash: Round 8, 2012 - Blues 23 - 29 Sharks, Eden Park, Auckland

Preview: The Sharks could do some serious damage to the Blues' already slim hopes of qualifying for the play-offs with a win in this match. New CEO, former Sharks and Springbok Captain John Smit, has already made his presence felt on taking up the corner office at Kings Park, by announcing that New Zealander John Plumtree will not be at the helm past this season, despite having taken his teams to Currie Cup success and a Super Rugby final in the past twelve months.

Plumtree then took the equally curious and admirable step of ending his tenure with immediate effect, with the Sharks to now finish the season under the guidance of assistant coaches Grant Bashford and Hugh-Reece Edwards, with Brendan Venter set to join as director of rugby ahead of the Currie Cup. It will be interesting to see what, if any, effect this has on the team.

Blues coach, Sir John Kirwan, recognises the importance of this match in Durban: "If we can't win the next three then it depends what happens elsewhere, we will be waiting for people to lose around us. That's not ideal. The most important game for us is the Sharks, because that will keep us in touch."

Even if he's already sweating on other results - never a sign of confidence - a win this weekend could potentially surge the Blues back into the top six. A loss, though, would almost certainly put the line through them for 2013.

The cavalry is finally back for the Sharks, with a host of big names returning to action just before or during the June Internationals. There is also some interesting talk out of the Republic that Patrick Lambie may switch to inside-centre, with Butch James coming in at fly-half.

Tip: Sharks by 12

Bulls v Southern Kings, Loftus Versfeld Stadium, Pretoria

17:05 local, 15:05 GMT, 01:05 EST +1d, 00:35 CST +1d, 23:05 WST

Head to Head: Played 1; Bulls 1, Kings 0

In Pretoria: First match between these teams at this venue

Last clash: Round 10, 2013 - Kings 0 - 34 Bulls, Nelson Mandela Bay Stadium, Port Elizabeth

Preview: A big win for the Bulls at home would go a long way toward sewing up the South African conference, and push them onwards toward a top-two finish overall and home-ground advantage heading into the semi-finals.

The major news out of Loftus this week has been that Bulls captain, Pierre Spies, has been ruled out for the rest of the season, after tearing a bicep while playing for South Africa against Samoa in the final of the Quadrangular Tournament last weekend. Spies underwent surgery on Tuesday, and the recovery period required will knock him out of action for both the Rugby Championship and the Springboks' Spring tour to Europe.

This was already on top of news that hard-working backrower Arno Botha had also been ruled out for the season after rupturing knee ligaments in the Springboks win over Scotland in Nelspruit. Botha and Spies had been the Bulls' top two tacklers for the season, creating a major hole in their defensive patterns for the rest of the Super Rugby season.

The Kings are not without injury trouble themselves, with their captain, Luke Watson, also out of action for six months with an ankle injury. Inside-centre Andries Strauss will captain the Kings for the remainder of the season.

The Kings are essentially unchanged from the side that played the Stormers on June 1, with Michael Killian coming in for Siviwe "Shakes" Soyizwapi on the right wing, and Shaun Venter starting at scrumhalf. Nicolas Vergallo will come off the bench.

Tip: Bulls by 17

Stormers v Cheetahs, Newlands Stadium, Cape Town

19:15 local, 17:15 GMT, 03:15 EST +1d, 02:45 CST +1d, 01:15 WST +1d

Head to Head: Played 10; Stormers 7, Cheetahs 3

In Cape Town: Played 5; Stormers 4, Cheetahs 1

Last clash: Round 10, 2013 - Cheetahs 26 - 24 Stormers, Free State Stadium, Bloemfontein

Preview: The Cheetahs absolutely must win this game, ideally with a bonus point to remain in touch with the Bulls in the hunt for the South African conference lead. Their nine wins in 2013 is already a record for the franchise, and while Free State finished seventh in the old Super 12 in 1997, the Cheetahs have never finished higher than 10th overall, since they re-entered the competition with the expansion to Super 14 in 2006.

But the Stormers remain the best defensive side in the competition, and so just scoring one try - never mind four - will be a tough ask. The Stormers have only let in 17 tries in 2013, while the best defensive side in the top six currently, the Reds, have let in 21. As the best South African sides in the competition, the Cheetahs and Bulls have let in 28 and 27 tries respectively.

That said, a major opportunity exists for the Cheetahs, with Stormers and Springbok Captain Jean de Villiers finally succumbing to his crammed playing schedule and having a week off. While also one of the few strike weapons the Stormers have gone to this season, de Villiers is also their defensive lynchpin, something the unpredictable Cheetahs would be mad not to explore.

Willie le Roux, Adriaan Strauss, and prop Trevor Nyakane have all impressed in their time in the national set-up, and it will be interesting to see how that translates back to the Cheetahs. For not the first time this season regarding the Cheetahs, I find myself sniffing an upset.

Tip: Cheetahs by 5

Byes: None - the Australian conference remains in its June recess for the British & Irish Lions tour.

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