The Frenchman leaves Selhurst Park with Palace bottom of the Premier League after a run of four consecutive defeats, the latest a 3-1 loss at home to Liverpool. The club have collected just seven points from their opening ten league fixtures and conceded 24 goals, the highest total in the division.
According to the BBC, Frank has emerged as the leading candidate to take over, with discussions between the former Brentford and Tottenham manager and Palace advancing. Frank has been out of work since leaving Tottenham in February and is understood to be interested in returning to management.
Crystal Palace confirmed Sage's departure in a statement, announcing that three members of his coaching staff – Jamal Alioui, Damien Della Santa and Sandy Guichard – had also left.
"The club thanks Pierre and his staff for their efforts during their time in South London, and wish them well for the future," the statement read. Palace added that an update on the appointment process would follow in due course.
Sage was appointed in June on a three-year contract after Oliver Glasner departed at the end of last season. The 47-year-old arrived with an impressive reputation following his work in France, where he led Lens to a second-place finish in Ligue 1 and the club's first Coupe de France triumph in their 120-year history.
However, he struggled to reproduce that success in south London. Palace's league losing sequence began with a 5-0 defeat against Brighton and has left them without a Premier League victory since 11 October. Their difficulties have extended into Europe, where they sit 21st in the 36-team Europa League table after winning one of their first four matches.
The contrast with Glasner's achievements has been stark. The Austrian guided Palace to their first FA Cup triumph and a Europa Conference League title before leaving at the end of the previous campaign. He is now in charge of Nottingham Forest.
Sage is the second Premier League manager to lose his job this season, following Manchester United's dismissal of Michael Carrick. Palace will now look to make a swift appointment during the international break, with their next league fixture away to Coventry City on 21 November.
Frank's experience in the Premier League makes him an attractive candidate as Palace attempt to arrest their slide. He previously established Brentford in the top flight before taking charge of Tottenham, and the club will hope a change of leadership can improve a defence that has been badly exposed during Sage's short tenure.