CAPE TOWN: South Africa captain Faf du Plessis believes the new World Test Championship will add "proper context" to the five-day game and has backed the introduction of the global league as a step forward for the sport.

The championship starts on Thursday when England host Australia in the first Ashes test and will see the top nine five-day nations face-off over a two-year period, scoring points based on their success and culminating in a final at Lords in June 2021.

"For the last while we have longed to have something to play for that gives proper context to test cricket," Du Plessis said in a press release from Cricket South Africa.

"The stakes are high because every series matters. It’s refreshing and the players we are looking forward to this new chapter of test cricket."

Du Plessis feels the five-day gave has been given a boost by the introduction of the format.

"I feel test cricket is in a healthy state," he said. "The players who play all three formats will attest to the fact that test cricket is the purest format of the game and it is still the number one format.

"The younger generation may enjoy the hustle and bustle of T20 cricket but when a test match goes down to the final hour on the fifth day, that entertainment is hard to beat."

South Africa start their championship campaign away with three tests in India in October, before welcoming England for four matches over the New Year.

"We have a tough assignment to start with against India away. We beat them at home last season but playing against India in India is probably one of the toughest challenges for an international player.

"We then have the current world champions England at home, this is always a cracker of a series during our summer and one that we look forward to. We probably have the toughest start, but everyone will play everyone, so it doesn’t really matter."

South Africa will in fact only play six of the eight other nations in the championship, and also have two-test series against West Indies (away), Pakistan (away) and Sri Lanka (home), and three tests against Australia (home).