The Dutch coach had become Spurs' first choice only for the Eredivisie leaders to persuade Slot to give the club at least one more season, since they have qualified for the Champions League.
It is also understood that questions were raised about Tottenham’s current structure as they also seek a director of football, and Slot had issues with how he would work in that system.
While the feeling in the game had been that the Slot negotiations were close to the finish line, some figures with knowledge of the situation insist Spurs were still conducting discussions about a top list of targets. One of those is Postecoglou, who is being strongly considered, along with Sporting's Ruben Amorim.
Daniel Levy would greatly value Luis Enrique but that is seen as more difficult to pull off given the Spanish coach's list of demands when Chelsea interviewed him.
Postecoglou has earned huge admirers in the game for his expansive and entertaining work at Celtic, and there is hope that any deal would be smoother to do than with Feyenoord due to good relationships between involved parties. The Australian is commonly seen as one of the most exciting managers in world football.
Ryan Mason is currently in charge to see out the season, having taken over from Cristian Stellini who was dismissed following a thrashing at the hands of Newcastle. Stellini himself was only an interim in the role, following the sacking of Antonio Conte earlier this season.
Spurs face relegation-threatened Leeds on the final day of the season and sit eighth in the Premier League table ahead of the weekend, a position which would see them miss out on any kind of European football next term.
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