Spurs captain Son has scored 173 goals in 451 appearances across 10 seasons in north London but failed to end the club’s 17-year trophy drought.
The South Korea forward suffered painful defeats in the Champions League final against Liverpool in 2019 and the League Cup showpiece against Manchester City four years ago.
But hopes next Wednesday’s all-English clash with United in Bilbao will be a more joyful experience.
While Ange Postecoglou’s team have endured a torrid Premier League campaign, they have saved their best for Europe to reach the first final of the Australian’s turbulent two-year reign.
During an interview with Korean media at the club’s Europa League final media day on Monday, Son said: “We’ve been talking about this for years. The biggest reason I stayed at Tottenham was because I wanted to do something others couldn’t achieve.
“That’s probably why I’m where I am now. You need all the pieces to complete a puzzle. I think I’ve gathered all the other pieces to make that puzzle complete.
“It feels like I’ve been missing that one most important final piece and I’ve been trying to find it for the past 10 years. I really hope I can finally complete the puzzle this time.
“It feels different this time. I really want to win – more than anyone else, I think. So many people are supporting us with the same desperate passion I feel. If we prepare well, I believe we can achieve it.”
Son has watched former Tottenham team-mates taste success elsewhere after leaving the club, with Harry Kane the latest after he helped Bayern Munich to the Bundesliga title earlier this month.
The duo struck up a formidable partnership at Tottenham and while Kane left almost two years ago, his success has given Son “energy” before the showdown with United in Spain.
“I actually texted Harry and he called me back on a video call! I was really happy to see him happy,” Son said.
“He is one of my best friends and to see a once team-mate achieve so much, I was delighted for him like he’s my family. With that positive energy, I hope he can support Spurs in the game as well so we can achieve a good result like his.
“For me, every game is special and every game is meaningful, but this game feels like an opportunity that may not come back.”
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