Mauricio Pochettino claims Heung-min Son would no longer be at Tottenham had he not pushed for the South Korean to be cleared for Asian Games duty in 2018.
The forward had committed to a new contract with Spurs shortly before being called up for the crucial international event.
Son and his compatriots had been assured that they would be spared mandatory 21-month military service if they claimed gold medal glory at the Asian Games.
Premier League giants Tottenham were initially reluctant to part with a prized asset, as he was required to aid their domestic efforts.
Pochettino, though, was aware of how important the event was for Son and what it could mean for his future, and fought hard to keep the 27-year-old happy and committed to Spurs.
The Argentine, who parted company with Tottenham in November 2019, told the High Performance Podcast: “With Harry Kane injured, Son not playing the first few months because of the Asian Games, no one talks about that.
“Today, Sonny is at Tottenham because we allowed him to go and play two competitions that weren't compulsory, not being selfish and saying, 'No, Sonny needs to stay here'.
“If not, two years and you need to stop the contract with Son.
“No one says anything about that. It was our decision to provide him the time to go.”
Son remains an important figure at the Tottenham Hotspur Stadium, while Pochettino is waiting on offers to entice him back into the dugout.
He guided Spurs to the Champions League final last season and another top-four finish, but was relieved of his duties and replaced by Jose Mourinho after overseeing a tough start to the 2019-20 campaign.
On how things started to unravel for him, Pochettino said: “Monday [after the final], I was thinking to build again, because when you are so competitive and you are a winner, you are not stuck in the past. You lose, but you want to win again tomorrow.
“I wasn't knocked because we didn't win the final, we wanted to take a massive experience for us, learn and be ready again for the next season.
“We were fighting for the top four at the same time we were fighting to be in the Champions League final.
“If you lift the trophy, you are very successful. But second is a failure, no? We are not thinking like this but, of course, that makes you sad.
“Of course people recognise the job was fantastic, but to finish winning the Champions League would have been amazing.”