Atletico Madrid striker Diego Costa appeared to poke fun at the coronavirus outbreak which is currently sweeping the world by "faking coughing" in front of journalists.
The World Health Organisation (WHO) on Wednesday declared coronavirus a global pandemic, while positive diagnoses in Spain - where Costa plays for Atletico - passed 2,000.
The latest figures show more than 12,500 people have tested positive with 4,616 deaths.
European football has reacted to the escalating situation by playing a number of matches behind closed doors, while Juventus defender Daniele Rugani became the second professional player to test positive for Covid-19.
Just a couple of hours after helping Atletico knock holders out of the competition, the divisive former Chelsea forward walked past journalists at Anfield while "theatrically" coughing.
"Diego Costa just walked through the mixed zone fake coughing at everyone as he went down the line," Press Assocation's Carl Markham tweeted.
"Not particularly funny or appropriate."
"Not nice," La Repubblica's Antonello Guerrera posted. "Not funny either." Daily Mail's Dominic King tweeted: "He was the only who laughed."
