South Korea's K League said that it feels disappointed and cheated by Juventus over the Serie A club's refusal to apologise for forward Cristiano Ronaldo sitting out a pre-season friendly in Seoul last week.
Ronaldo was contracted to play at least 45 minutes against the K League All Stars, according to event organisers, but was advised to rest by Juve's medical staff due to "muscle fatigue" from a match played 48 hours earlier in Nanjing.
The K League, on Tuesday, sent a letter of protest to Juve over the alleged contract violation and Juve chairman Andrea Agnelli responded on Wednesday by denying that the Italian champions had acted irresponsibly, but did not apologise.
On Thursday, the K League said Juve's response was filled with "untruth and deception" and demanded an apology.
"K League clearly registers our profound indignation and disappointment to Juventus' irresponsible behaviour and manners, and we strongly urge Juventus to offer a sincere apology and explain the reason for Ronaldo's no-show," the league said.