Tottenham Hotspur run the risk of losing out on 75% of their Seoul pre-season tour fee if a big transfer goes through in the coming weeks.For football clubs, knowing when to part ways with players who have been standout performers over an extended period is a skill in itself.Clubs let legends go so new ones can emerge, and Tottenham Hotspur now find themselves in a position where one of the club’s most recent legends, Heung-min Son, could leave.The Korean winger has given the best part of a decade to Tottenham, and his loyalty was greatly rewarded at the end of last season, when Son hoisted the Europa League trophy high under the lights in Bilbao, Spain.Credit: @shooting.practice on InstagramTottenham could miss major commercial fee if Heung-min Son is absent from Asia tourThe Telegraph have now reported that Tottenham would lose as much as 75 per cent of their agreed fee for playing in Seoul if Son is not part of the touring squad.It is further noted that the fee would only hit 50% if Son travels with the team but does not feature in the match for Spurs in front of the local crowd.Son is now 33 years old and has 12 months remaining on his current Tottenham contract. The Korean is also Spurs’ highest earner, but there is chatter that Son could leave Tottenham this summer if a strong offer arrives.It is understood that the club’s captain will not be forced out, but will be allowed to decide whether or not to leave on his own terms.Son’s future hangs in the balance as Spurs prepare for pre-season tourTottenham are expected to jet off for their pre-season tour of Asia on Sunday, where they are set to face Arsenal in Hong Kong on 31 July and Newcastle United in Seoul on 3 August.As things stand, Son looks set to be part of that pre-season tour, despite interest in Son’s services from clubs in America, Europe and the Middle East.The club’s captain has already featured under new boss Thomas Frank in Spurs’ first pre-season fixture against Reading last Saturday.Barring any serious injury to the Korean star, Son is expected to be involved in both matches on the Asia tour, with his long-term future likely to be resolved once the team return to the UK.READ MORE: Tottenham Hotspur and Newcastle are alert to Aston Villa midfielder this summerThe post Tottenham could lose 75% of pre-season appearance money under one condition appeared first on Spurs Web.