Manchester City Director of Football Txiki Begiristain has left the Premier League outfit after 13 years and will be succeeded by Sporting's Hugo Viana, the club revealed on Thursday.
The 60-year-old Spaniard has been a major part of a trophy-laden period for City during which they won seven Premier League titles, two FA Cups, a Champions League and a Club World Cup.
Begiristain previously served as Barcelona's Director of Football for seven years until 2010.
His departure from the Etihad has raised questions over manager Pep Guardiola's future at the club.
Begiristain and Guardiola have worked closely together at City.
The 54-year-old Guardiola's current contract ends after this season and the Spaniard's plans remain uncertain.
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