Last updated on .From the section Rugby Union

England and Saracens number eight Billy Vunipola has suffered a series of injuries in 2018, including breaking his arm three times

The next three English domestic rugby union seasons will be extended and also include in-season breaks, with players limited to a maximum of 35 matches per campaign.

The measures, beginning in 2019-20, are designed to protect players during a demanding schedule that includes the 2019 World Cup and 2021 British and Irish Lions tour of South Africa.

Apart from during a World Cup year, the Premiership season will start in early-to-mid September and finish in mid-to-late June.

For the first time, there will be guaranteed breaks for players in a bid to improve player welfare, with penalties for clubs who breach the policy.

But while the game limit for England players has been cut from 32 full matches to 30, some could be involved in as many as 35 games.

Analysis

BBC Radio 5 live rugby reporter Chris Jones

Despite protestations from the players last year, the season has been extended, running now from mid or early September to mid or late June, meaning rugby in England will be played near the height of summer from 2020 onwards.

While the authorities have stressed the introduction of formal in-season 'rest periods' for players, especially around the developmental competition the Premiership Rugby Cup, in reality the better-run clubs do this anyway.

Worryingly, nothing especially has changed for England internationals, for whom the pre-arranged rest periods don't apply. While the game limit has been slightly reduced, a top player could still be involved in up to 35 high-intensity matches per campaign.

The players' union has welcomed some of these moves, but admits there is still a way to go. Despite Tuesday's developments, the issue of player welfare and injury rates in the game is unlikely to go away.

It has also been confirmed England will take a weakened squad on the tour to Japan in 2020, with the 2019 Rugby World Cup squad rested for those summer Tests if they have had 20 or fewer match involvements in the 2019-2020 season.

A match involvement counts as 20 or more minutes. Research indicates 35 or fewer match involvements reduces the risk of injury.

The key announcements include:

Guaranteed in-season breaks for players in each of the three seasons.

Mandatory five-week post-season rest for all players, which includes two weeks' absolute rest and three weeks' active rest.

Minimum 10 weeks off/pre-season for players in the England Senior Elite Player Squad.

Minimum 12 weeks between the Premiership final and round one of the following league season.

Maximum 35 match involvements (more than 20 minutes) in any one season for all players.

Maximum 30 full game equivalents (reduced from 32) in any one season for all players.

England players to have a mandatory rest week if playing all international matches and more than 65% of total minutes (reduced from 80%).

A number of high-profile players spoke out last year about Premiership Rugby's plans to extend the season, with the Rugby Players Association vehemently opposing the proposals.

However, while the season has not been extended by a full month, the Premiership campaign will nevertheless run over a longer period.

For example, the 2020-2021 season will run from 12 September to 26 June.

However the authorities point to in-season rest period, and a protected pre-season as a compromise.

"This new agreement gives players guaranteed in-season breaks for the first time and reduces playing thresholds, while protecting the five-week post-season break that was already in place," said players' boss Damian Hopley.