Darley has lost superstar brothers Brian and Nick Graham.
The Grahams will play with West Footscray in Western Region Football League division two next year.
Brian Graham leaves after three decorated years with the Devils.
He was a prime mover in Darley's 2017 Ballarat Football League premiership, when he teamed up with another brother Chris.
The midfielder was a club best and fairest, BFL inter-league representative and three-time BFL team of the year member.
Nick Graham joined the Devils after losing his place on Carlton's AFL list at the end of last year, reuniting with former Blues teammate Heath Scotland at Darley Park.
While the Grahams were contracted to continue with Darley, club secretary Lorissa Edwards said the Devils had no issues with releasing them and wished the brothers all the best.
She said meeting the needs of a young family and work commitments had led to Brian's decision to play much closer to his home.
Edwards said Graham's circumstances would have made it difficult for him to fully meet the demands of playing with Darley, such as getting to all training sessions.
She said he was not the type of player to make compromises.
Before deciding on the move to West Footscray, Graham had considered taking next year off football.
Edwards said Nick wanted to continue playing with his brother.
The departure of the Grahams follows the loss of coach Heath Scotland, who has taken up a development coaching role at North Melbourne in the AFL.
Brian Graham was one of the first recruits Scotland attracted to Darley, with him having played with Wyndhamvale in the WRFL.