That's the view of Tottenham Hotspur coach Nick Montgomery, who insists the Australian still tunes in to watch his ex-team play.
Montgomery, who managed Hibernian prior to his move down south to Spurs, revealed that the 59-year-old head coach keeps tabs on Brendan Rodgers' side, despite leaving Scotland in 2023.
In an interview with the Daily Record, Montgomery heaped praise on the Spurs coach, whose future is set to be decided this week by chairman Daniel Levy. "Ange loved his time at Celtic," he said.
"I think he cherishes those times at Celtic, as it's a massive club. It’s used to winning, and when you go in there, the pressure is on that you continue that trend, and you have to win. Probably, people doubted him, but Ange managed to do that.
"He's always watching the Celtic games and the A-League games, and the Japanese games. We always have them on in the coach's office. He obviously really enjoyed his time there, and no doubt he's really happy for the success again this year.”
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Montgomery continued: "He's obviously been massive in this cup win (Europa League). Look, he's a great guy, and I think he's a man who's full of self-belief. He's been around the world and won trophies.
"To work alongside him and get the opportunity to come to a club like Tottenham in the Premier League and Europa League, he always had the self-belief that we could do something special this season.
"It was a special moment for the club, a club without a trophy for a long time."
Last month, Spurs defeated Ruben Amorim's Manchester United side 1-0 in Bilbao, thanks to a first-half goal from Brennan Johnson.
It was the club's first trophy in 17 years.