Keith Edelman, the Arsenal managing director, has resigned from his role to go "in search of a fresh challenge".

Edelman, who has been at the club for eight years, has announced he will leave his post as a director of Arsenal Holdings PLC, although he will continue to work with the club for a further 12 months to ensure there is a smooth transition for his replacement. In the wake of Edelman's departure Ken Friar, a former managing director at the club, has assumed the role of acting managing director.

"I have thoroughly enjoyed my time at Arsenal," Edelman said. "It has been a very exciting period for the business and I am proud to have contributed to the club's many off-field achievements over the past eight years, not least the Emirates Stadium project. Now that we have completed our second season at Emirates, I believe it is the right time to seek pastures new and embark upon fresh challenges."

Peter Hill-Wood, the Arsenal chairman, expressed his gratitude to Edelman. "Keith has played a major role in the growth of the club since he joined in 2000," he said. "In that time we have successfully implemented the move from Highbury to Emirates Stadium that has underpinned the future of the business and confirmed our position as one of Europe's leading clubs. We are grateful to Keith for his crucial role in this transformation. Under Keith's stewardship the club has achieved record profits and the board owes him a debt of gratitude for his contribution. We wish him the very best for the future."

A statement from Arsenal Holdings PLC said: "The board has already initiated the search for a new managing director and will update shareholders and stakeholders when appropriate. In the meantime, director Ken Friar, who has a wealth of football-based experience and business acumen having previously occupied the role of managing director (1982-2000), will assume the position of acting managing director."