JOHANNESBURG, SOUTH AFRICA - APRIL 12: Lwazi Mvovo of Sharks charging past Willie Britz of Lions to score his try during the Super Rugby match between Lions and Cell C Sharks at Ellis Park on April 12, 2014 in Johannesburg, South Africa. (Photo by Gallo Images)

Sydney – The Sharks and defending champions Waikato Chiefs face testing Easter derbies, while Wallaby ace Israel Folau returns to bolster the NSW Waratahs in this weekend's Super 15 rugby.

Jake White's Sharks tackle the Central Cheetahs in Durban on Saturday, while the Chiefs host seven-time Super Rugby champions Canterbury Crusaders in a blockbuster New Zealand derby.

The Australian Rugby Union said they would not be blocking Folau from playing his first match in a month after controversially stepping in last weekend and making him unavailable because of a lingering throat injury.

The Waratahs went down to the rejuvenated Western Force last week in Folau's absence after splitting their two tour games in South Africa.

The Sharks lead the southern hemisphere provincial series by two points from the ACT Brumbies, who along with the Queensland Reds and Otago Highlanders are having the Easter round off with a bye.

The Durban-based outfit usually have problems with the Cheetahs and have lost three of their previous six home games against the Bloemfontein franchise.

The Cheetahs welcome back Springbok flanker Heinrich Brussow, who has had a lengthy absence with a toe injury.

“We are glad to have him back in the thick of things, especially with Lappies Labuschagne out injured. He (Brussow) will be a key factor at the breakdown area this weekend,” coach Naka Drotske said.

The Chiefs have been struggling in recent weeks with two high-scoring draws in South Africa and labouring to put the Melbourne Rebels away at home last week.

Yet the Waikato back-to-back champions are three points off the lead and coach Dave Rennie believes his team are not far off reaching their best form.

Previous clashes with the Crusaders generally bring out the best in the Chiefs and Rennie is anticipating the same to happen on Saturday in Hamilton.

“We're up for it,” Rennie said. “Crusaders-Chiefs games have been huge in the last couple of years and, in Tanerau Latimer's 100th game for the Chiefs, there are a number of motivating factors for us to front.”

The Waratahs were simmering over the ARU intervention last week to pull Folau out of the match against Western Force in Perth overriding the team's medical staff on the state of the prized fullback's bruised throat.

The Waratahs, fifth overall, line up against South Africa's Northern Bulls in Sydney on Saturday looking to end an eight-match losing run against the Pretoria-based Bulls, including the last three at home.

The Tahs are looking to eight-try Folau to ignite an unchanged backline with halves Nick Phipps and Bernard Foley playing for their eighth straight game together.

Lock Flip van der Merwe has been passed fit to face the Waratahs after recovering from an arm injury suffered in last weekend's bonus point loss to the Highlanders in Dunedin.

“We are very keen to get back on the winning trail. We have played well in patches, so we will be looking for a solid performance in Sydney,” coach Frans Ludeke said.

Western Force have a string of injuries as they attempt to chalk up their sixth straight game against the Rebels in Melbourne on Good Friday.

Scrum-half Alby Mathewson (ankle) and winger Luke Morahan (hamstring) are set to miss the game, while fullback Jayden Hayward (personal reasons) is another unlikely starter.

A decision has to be also made on the fitness of forwards Pek Cowan (leg) and lock Sam Wykes (ribs).

In this weekend's other games, the Western Stormers host the Golden Lions in Cape Town and the Hurricanes take on the Auckland Blues in Wellington. – Sapa-AFP