Six Nations: Scotland will not agree to six-week tournament - Mark Dodson
Scotland will fight plans to reduce the Six Nations to a six-week tournament.
England's Rugby Football Union hopes to remove one of the two fallow weekends when games are not played, to create space for the new global season.
But Scottish Rugby's chief executive Mark Dodson says such a move would be a threat to player safety.
"My view is that seven to six weeks is a retrograde step and it's a dangerous step as far as player welfare is concerned," Dodson told BBC Scotland.
Dodson also insists the unions in Ireland, Wales and Italy share his view.
"We're going to look after our boys," he said.
"Anybody who has just witnessed the intense physicality in this last Six Nations and wants to reduce that down to six weeks is taking a huge gamble with player safety.
"There will be discussion over the next month and we're very clear of how we feel. I'd imagine other people will be equally clear and will share our views."
'Smaller nations will be compromised'
Ian Ritchie, the RFU chief executive, plans to lobby for change when the review of the championship takes place in April, suggesting the new format is introduced after the 2019 World Cup.
Dodson also shot down the proposal on the basis of player resources.
"Nations with smaller player pools are going to be compromised and hit far harder by a six-week competition," he added.
"So you're going to make the Six Nations championship less competitive at a time when the tournament is at an all-time high in terms of popularity and broadcast revenues."
Scotland won three games in this year's tournament for only a second time in the Six Nations era, and the first since 2006, but still finished fourth for the second year running.
'These decisions rarely seem to have player welfare at heart'
Former England captain Lewis Moody fears rugby's powerbrokers put money and scheduling logistics ahead of player safety when making key decisions.
"I think the decisions made around the number of games played rarely seem to have the players' best interests at heart," the ex-flanker told BBC Scotland. "A lot of those decisions are made from a financial point of view.
"It seems to be more about, how many games can we fit into the season and how can we make everything flow more smoothly, which I understand is important.
"But international rugby is incredibly demanding, the amount of physical and mental strain the body goes through, and after an international window the players drop straight back into European rugby, which is on a par with international rugby in its intensity.
"So for the players to have less time off during that period is a big ask. Have they looked in-depth into the impact on the players and the amount of time off they're getting?"
Moody, who won the Rugby World Cup with England in 2003, and toured New Zealand with the British & Irish Lions two years later, believes elite players also need respite from the psychological stress of the sport.
"Taking away from the physical side, that mental pressure you're under to deliver consistently on the international stage," he said. "You're in front of a huge number of people, your mates and coaches, you want to deliver and get it right time and time again.
"To deal with that mental pressure and stress and other things going on in the media, all that load takes a toll on a player - all those things need to be considered.
"The players put themselves out there for the viewing public, for their country, for the powers-that-be, and they need to make sure they're taking absolute quality care of them."