The Spurs star been one of the revelations of the 2018-19 season and has scored in his last four games in all competitions, taking his tally to 16 goals in 32 appearances.
And Son explains that despite the heavy match-load he has endured in recent months, with the South Korean having featured for his country at the Asian Cup, his love of the game keeps him going and encourages him to give his best.
“I’m just trying to enjoy every moment," Son said.
"Honestly, there’s no better thing than football for me, and I’m happiest when I’m playing football.
“I don’t have much stress really, but I get rid of stress by playing football. I think that is how I can keep going.
“I have no issues with my fitness level at the moment.
“Sometimes, when there are some hard times for me, I can still keep thinking about football. I always feel thankful for having a chance to play football.”
Son, primarily a winger, has often been used up front of late by manager Mauricio Pochettino as he seeks to replace the injured Harry Kane's goals.
And the 26-year-old has repaid his manager's faith in him when playing as a striker, scoring seven of his 16 goals from his 10 appearances as a centre-forward.
Pochettino will be confident of progression in that tie, with Spurs currently 3-0 up from the first leg courtesy of goals from Son, Jan Vertonghen and a late Fernando Llorente header.