The 40-year-old will be reunited with ex-Oxford United captain Adam Murray, who was appointed assistant boss in March, after leaving Port Vale, where the pair had worked together following Whitehead’s retirement in 2018.
In 2004, Whitehead signed for Sunderland on a free transfer, with the club in the Championship at the time, on a three-year contract with the club.
However, Sunderland were ordered to pay £150,000 to Oxford at an FA tribunal to compensate for his development. Oxford would also receive 25% of any fee should Sunderland sell Whitehead. Whitehead was later to become club captain under former boss Roy Keane.
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That fee turned out to be somewhere in the region of £3million to £5million after the midfielder joined Stoke City back in 2009 after making 200 appearances for Sunderland in all competitions over five seasons, winning promotion to the Premier League on two occasions.
Following four seasons at Stoke City, Whitehead joined Middlesbrough and then Huddersfield Town before retiring during the 2017-18 season and has now joined the coaching staff at Besiktas, who are one of Turkey’s biggest clubs and are managed by ex-Barnsley and West Bromwich Albion boss Valerien Ismael. Besiktas have won 21 top-flight titles in Turkey but finished sixth last season.
Speaking to Port Vale’s official website, Whitehead said: “This opportunity is something I couldn’t turn down and I’d like to thank the club for being supportive and allowing me to do this.”