Saracens director of rugby Mark McCall has warned that professional club rugby in England could face the same perilous fate as county cricket, if plans for an 11-month season are implemented as part of the new global calendar for the international game.
World Rugby announced last month that the new global season will see the test window for summer tours switched from June to July, while future British & Irish Lions tours are expected to finish in August from 2021.
Premiership Rugby has already revealed it plans to retain the traditional September start to the domestic campaign and switch their showpiece final from May to the end of June.
McCall, however, has serious misgivings about the prospect of an 11-month season.
"To my mind, you've got three competing interests - player welfare at the front of it, then you've got international rugby and club rugby," said McCall.
"If the season is going to finish at the end of June, then to start in September doesn't seem the right thing to do. The internationals players come back at the end of July, and where does that leave them in terms of recovery and that kind of thing?
"County cricket used to be quite important and it is gone," he added. "It is a very young professional sport - rugby union - and I think the club game is just finding its feet, and you need to be careful that it must retain its significance."