Premiership players could go on strike because of extra demands on them, says former Rugby Football Union director of professional rugby Rob Andrew.
Proposals to extend the Premiership season by a month from the 2019-2020 campaign have been opposed by players.
“What’s giving in is the players’ bodies – that’s not sustainable long term,” Andrew, 54, told BBC Sport.
“Something will give and eventually if the players decide not to turn out, then there isn’t much of a product.”
Exeter chairman Tony Rowe said at the start of October that the plans would result in a more balanced season for club players.
However, leading coaches have voiced concerns about reducing the length of pre-season, and the effect it could have on player welfare.
“We’re trying to fit too much in with the same players being asked to repeat over and over again in a very demanding sport,” added Andrew, who was director of professional rugby with the RFU from 2011 to 2016.
“I think the players will have a big say over the next 12 to 18 months to try to find this holy grail.”
England and Saracens number eight Billy Vunipola – out for four months after injuring his knee – has said he would take a pay cut to play less rugby and believes players are at risk of “burning out”.
Chris Jones, BBC Radio 5 live rugby union commentator
Having been on both sides of the fence, Andrew is well placed to comment on the various tug-of-wars prevalent in English professional rugby, and although his tenure at the RFU has been justifiably criticised, smoothing the relationship between club and country was Andrew’s finest achievement.
However, by acknowledging that strike action is not out of the question, Andrew clearly believes the disconnect between administrators and players is as wide as ever.
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