First Division clubs have rowed back on boycott threats and will play Shamrock Rovers II “under protest”.
“Many of our fans would have preferred us to boycott matches against any ‘development’ team,” a statement from the other nine second tier clubs read.
“But the potential sanctions we may face could put the very future of our clubs in jeopardy.”
The FDA says it considered court action to boot the Hoops out, but it would have delayed the start of the season.
“Our clubs will play against a ‘B’ team for the 2020 season, but for the 2020 season only,” the statement added,
“However, our clubs will participate in the 2020 season under protest.”
Dundalk and St Pat’s have already explored entering second-string teams in the First Division from next season.
This year, a compromise was reached whereby Rovers can only play one outfield player and a goalkeeper from their first-team squad in the First Division team.
It was to be three outfield and a goalkeeper.
But a rival's request to prevent Shamrock Rovers II playing 18-year-olds and younger was rejected by the FAI.
The FDA statement added: “We’ve already seen a number of very young players from various clubs joining Shamrock Rovers on the promise of ‘B’ team action in our league.
“This brings into question the very purpose of Academies and their role in Irish football.”
