Patterns are emerging and the elastic bands that have held teams together are being stretched in Super Rugby

It's a tough weekend in Super Rugby. The Bulls are up against it. The Stormers face a potential banana peel in Singapore.

The Sharks could be mugged in Bloemfontein and the Lions have everything to lose against the Southern Kings.

That’s the situation for South Africa’s Super Rugby participants this weekend as the tournament begins its second month.

After four rounds patterns are emerging and the elastic bands that have held the teams together are stretched to breaking point.

• Waratahs snatch comeback win at the death against Rebels Centre David Horowitz scored a try in the final minute to cap a second-half fightback to give the NSW Waratahs a thrilling 32-25 win over the Rebels in Melbourne on Friday. 

It’s the stage of the season where the pretenders will start to fall away and the potential winners will surge ahead. The Bulls have made a poor start to the campaign‚ recording their first win of the season against the Sunwolves at Loftus last week.

It was an unconvincing victory‚ but they were down to 14 men for more than half the match after flank Renaldo Bothma’s red card.

Under those circumstances any win is a good win. But the Bulls will have to be much better if they hope to get their season on track against the Blues in Auckland.

The return of former Bok skipper Adriaan Strauss at hooker and the reunion of Bok centres Jesse Kriel and Jan Serfontein is some positive news.

• Barrett impresses as Crusaders grind out win over ForceScott Barrett underlined his versatility that should make All Blacks coach Steve Hansen take notice as he produced a tireless effort at blindside flanker in the Canterbury Crusaders' 45-17 win over the Western Force in Christchurch on Friday. 

Serfontein will make his 50th Super Rugby appearance.

The Bulls‚ though‚ have only beaten the Blues once in 11 away games and although the Auckland franchise is struggling this season with one win in four matches‚ they are still formidable.

The Blues should have too much firepower to overcome a Bulls side that is already looking like an also-ran in 2017.

The Cheetahs against the Sharks promises to be the pick of the weekend’s matches from an SA perspective with two teams seemingly on the up.

• Bosch selected at flyhalf for the Sharks' crucial Super Rugby clash against the CheetahsSanity has seemingly prevailed in Durban with the selection of Curwin Bosch at flyhalf for the Sharks' crucial Super Rugby clash against the Cheetahs in Bloemfontein on Saturday. 

The Cheetahs need to a win at home and with the return of a host of key players such as wings Raymond Rhule and Sergeal Petersen‚ centres Nico Lee and Francois Venter‚ scrumhalf Shaun Venter‚ No 8 Paul Schoeman‚ lock Justin Basson‚ prop Ox Nche and hooker Torsten van Jaarsveld‚ they have a good chance to upset the form book.

The Sharks might have won three from four this year but two wins were against mediocre Australian opposition and the third against the struggling Kings.

This weekend will be their toughest test against a full strength Cheetahs. Curwin Bosch starts at flyhalf in Super Rugby for the first time and his performance and direction will be key to the Sharks’ effort.

Both packs are formidable‚ which means the match could come down to which halfback pair dictates from behind the big men.

• Sharks pose toughest challenge for CheetahsThe Cheetahs’ last Super Rugby home game for three weeks‚ against the Sharks this Saturday‚ is also their toughest test of the campaign so far and a match they simply have to win. 

The coaches’ box is also where this one might be won and lost.

Cheetahs mentor Franco Smith is not afraid of making innovative calls‚ such as a lineout that features wing Ryno Benjamin as a catcher and three backs in the set piece.

They used it against the Bulls a few weeks ago and it led to a try.

There will be more variations on that theme. There is a sense that the Cheetahs‚ by sending a second string team to play the Jaguares in Argentina last week‚ have targeted this match to reveal more of their playbook.

Stormers coach Robbie Fleck wants his side to create space for sevens flyer Seabelo Senatla against the Sunwolves in Singapore‚ but he knows that his pack will need to do the hard yards first.

• Bulls coach concede that they are underdogs against the BluesHistory will weigh heavily against the Bulls when they face the Blues at the QBE Stadium in a Super Rugby clash in North Harbour on Saturday morning as the Pretoria side have not beaten their hosts in New Zealand since 2013. 

The Cape side will have too much firepower for the Sunwolves‚ but only if second string locks JD Schickerling and Chris van Zyl are able to provide the same front-foot ball that the Stormers enjoyed from the rested Pieter-Steph du Toit and Eben Etzebeth over the opening three rounds.

After drawing the corresponding fixture last season there won’t be any complacency from the Stormers this time‚ and despite fielding a weaker team than they have all season‚ they should win going away.

Lions skipper Warren Whiteley will make his 50th Super Rugby appearance and it could be a long afternoon for the Kings in Port Elizabeth against last year’s finalists.

The Lions are starting to find the form that took them to the final weekend of Super Rugby in 2016 and coach Johan Ackermann has selected a full strength team to ensure there are no slip ups in the Bay.

- TMG Digital/TMG Sport