The Belgian manager replaced Welshman John Toshack in the top-flight Iranian club.
The 69-year-old Leekens started his coaching career in 1984 at Cercle Brugge and has also worked as head coach in Belgium, Hungary, Algeria, and Tunisia national football teams as well as Belgian clubs Anderlecht, Lokeren, Gent, Club Brugge, Kortrijk, Charleroi, and Excelsior Mouscron.
He inked the contract on Sunday and hours later entered Tabriz amid receiving a warm welcome from Tractor Sazi fans.
Upon arrival at Tabriz Airport, he expressed happiness for being in Iran and said that a great challenge awaits the team.
Tractor Sazi currently ranks fourth at IPL with 26 points from 15 games, being just five points behind the leading team, Sepahan.
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