Doncaster Rovers Belles will appeal against the Football Association's decision to demote them from the FA Women's Super League top tier in 2014.
The club has been a mainstay in the top flight for 22 years, in the newly-formed FA WSL since 2011 and the women's Premier League since 1991.
But next season they will be replaced by Manchester City Ladies.
"To say we are disappointed might be the understatement of the year," Rovers chairman Alan Smart told BBC Sport.
"We've had support from all over the world and people are angry and bemused at the decision.
"But we are built on a wider fabric than one big benefactor. Doncaster Rovers Belles are a massive community club. We are made of strong stuff and we will fight on."
As one of the founding members of the national women's league, Doncaster have twice won the league and FA Cup double and were synonymous as women's football grew in the early 1990s.
But from next season the summer league will expand to two divisions, with Manchester City joining seven other teams in FA WSL 1.
Having finished second from bottom in the first two WSL seasons, Doncaster will drop down a division to FA WSL 2 and compete against nine other sides.
The FA made its decision via an independent panel where clubs were assessed on their financial sustainability, where factors such as management, marketing and the quality of their coaching staff and facilities were considered.
Doncaster discovered the news after one game of this season, with boss John Buckley calling the situation "farcical".
The decision to split the league into two tiers, with relegation and promotion between both, is part of the FA's five-year plan to make women's football the second most-played sport in the country behind men's football.