JOHANNESBURG: Test cricket must adapt to survive in the face of the ever-tightening squeeze from shorter, more lucrative, forms of the game, both England and South Africa's captains said on Wednesday.

Calling for more structure in the cluttered cricket schedule, Alastair Cook and AB de Villiers agreed there is a growing tug on player commitments between the traditional format and Twenty20 competitions like the Indian Premier League (IPL) and Australia's Big Bash.

"I think it's a growing concern for the ICC (International Cricket Council) and they've been talking about it for the last few years," De Villiers, whose own workload between test cricket and his earning potential in the T20 format has been widely debated in recent weeks, said.

He reportedly earns $1.4m playing in the IPL for Royal Challengers Bangalore dwarfing his South Africa contract.

In a separate news conference on Wednesday ahead of the third test between the two countries at the Wanderers in Johannesburg, Cook said that while the five-day game still represented the ultimate test for a player, it could not risk standing still.

"Everyone loves test cricket, I believe," Cook said.

"We all know we have to protect test cricket. As the game progresses and evolves, you can't stand still.

"We have to always look to how we can improve the game. The people who run it must know there is a responsibility on their shoulders to look after it and try and push it forward."

DAY-NIGHT TESTS

The recent introduction of day-night tests in Australia is seen as a positive step, but De Villiers said the the Future Tours Programme, which determines bilateral cricket fixtures for the next six years, needed to be examined.

"I believe there are areas to improve and help keep the players focused in on the test game, he said.

"Obviously there are one or two (T20) tournaments going on around the world and financially you cannot ignore them because they do make a huge difference to our lives.

"You've got to look after that side as well but test cricket comes first. One or two things will have to change for the future."

On Monday, England's most successful bowler James Anderson said he would not be seeking to play in the IPL in order to rest for England's home test commitments against Sri Lanka and Pakistan from May to August.

"I'm at this stage of my career, I want to make sure I'm in good nick to play Test match cricket for England.

A couple of months' rest won't be a bad thing. My heart is with playing Test cricket for England," he told reporters.