A long-mooted league format in Test and one-day international cricket has been given the go-ahead by the International Cricket Council (ICC).
The proposals are due to come into force after the 2019 World Cup and will see nine teams play six series over a two-year period, with the two most successful sides entered into a play-off for the title.
Series must feature at least two Tests, but can have as many as five, as would typically be found in an Ashes series.
The ICC say the changes will help bring "context and meaning to bilateral cricket" with crowds dwindling outside of the sport's powerhouse nations for Tests.
A 13-team ODI league will commence in 2020 and "will be a direct qualification pathway towards the ICC Cricket World Cup".
ICC Chairman Shashank Manohar said: "This means fans around the world can enjoy international cricket knowing every game counts and in the case of the ODI league, it counts towards qualification to the ICC Cricket World Cup."
Four-day Tests will also be trialled on a bilateral basis until 2019.
South Africa and Zimbabwe have recently made a request to play a four-day Test - a solution often mooted in an attempt to speed up the longest format and make it more accessible to new fans.
ICC Chief Executive David Richardson said: "Four-day Tests will also provide the new Test playing countries with more opportunities to play the longer version of the game against more experienced opponents, which, in turn, will help them to hone their skills and close the gap with the top nine ranked teams."
