The South Korean national team really wants Son Heung-Min on this summer's Olympic roster, enough so that they're willing to make a deal to help Tottenham in their title race. The AP is reporting that Korea manager Uli Stielike is leaving Sonny off of the national team roster for two upcoming World Cup qualifiers later this month with the hopes that Spurs will let him play in the Rio Olympics.
"We've asked Tottenham to make Son available for the Olympics as a wild card, and in exchange, we offered not to select him for matches in March."
"Tottenham are in a battle for the Premier League title. Since our association is being considerate of the club, we hope they will give us a positive response."
– ESPN FC
Men's Olympic football requires that countries field a team of players that are 23 or under, but are allowed to choose three overage "wild card" players. Sonny is Korea's best player, but he turns 24 in early July, meaning he'd be one of Korea's wild cards. But there's a problem: the Rio Olympics run from August 5 to August 21, which would overlap with the beginning of the new Premier League season.
Stielike is pretty desperate to get Sonny on his Olympic roster, enough that he's willing to help Spurs win a Premier League title by not naming him to the squad upcoming WCQs against Lebanon and Kuwait in a couple of weeks if they're willing to let him to go Rio in August. Because the Olympics isn't a FIFA-sponsored event, Spurs can refuse to release their players for the competition if they feel it would adversely affect their domestic league performance.
There's an additional wrinkle to this story, though: South Korea LOVES the Olympics, enough so that it exempts male athletes that win medals in the Olympic games from participating in its country's mandatory military service. So there's additional motivation for Spurs to let Sonny go to Rio, and that might be enough to sway them. If there's a chance that by letting Sonny on the plane this summer they might win a title and get his military service waived, that seems like a pretty decent gamble to take.