Willian demanded "proper sanctions" be imposed on Dynamo Kiev after fellow Brazil international and former Shakhtar Donetsk team-mate Taison was racially abused by supporters in Sunday's Klasychne derby.
Taison led a Shakhtar counter-attack deep into the second half in Kharkiv before fouling Dynamo defender Artem Shabanov, to which the visiting fans in that corner of the stadium reacted with racist chants.
The forward reacted by showing his middle finger to those responsible and then booting the ball towards them, before referee Mykola Balakin ushered the teams off the pitch as per UEFA protocol, with Taison and fellow Brazilian Dentinho in tears.
Upon the teams' re-emergence a few minutes later, Balakin showed Taison a straight red card much to the former Metalist star's bemusement.
Shakhtar and their coach Luis Castro released strongly worded statements after the match and Willian – a former team-mate of Taison's at Shakhtar and with Brazil – urged the authorities to take "proper" action after the Ukrainian Premier League pledged to prosecute those identified as responsible.
Speaking ahead of Brazil's upcoming clash with Argentina, Willian said: "It's another sad episode for football.