Eyebrows were raised this morning at the news two female non-executive directors of Nine Entertainment were stepping down from the board.

Elizabeth Gaines and Holly Kramer are leaving — Gaines had been earlier named to the plum job as the chief financial officer of the iron ore exporter Fortescue Metals Group, while Kramer said she was quitting as part of changes to her board portfolio. Her other directorships include Woolworths and Australia Post.

The two resignations leave just four board members — chairman Peter Costello, former Nine chief executive David Gyngell, current CEO Hugh Marks and former Sky PLC exec Catherine West.

“Holly and Elizabeth have both been valued members of the board of Nine Entertainment during their time as directors,” Costello said in a statement to the ASX. “They have also made significant contributions as the Chair of the People & Remuneration Committee and Audit & Risk Committee respectively. I thank each of them for their excellent contribution as directors and wish them both much success in their future endeavours.”

It is rare to see two directors leaving a company board at once, let alone two high-profile female non-executive directors. Before the announcement, Nine’s board had equal numbers of women and men. Kramer especially would be in high demand for other senior board roles, such is her reputation. Gaines’ decision is easy to understand given the pressures as CFO of Fortescue and her need to devote all her time to her new role, but both leave Nine searching for new board members, with a plan to announce the replacements before Gaines and Kramer leave on February 3.