The Colombia international forward stepped off the bench to net a late equaliser for the Reds in their 1-1 draw with Luton.
After finding the target at Kenilworth Road, Diaz lifted up his top to reveal the words ‘Libertad Para Papa’ (Freedom For Papa) printed on a t-shirt underneath his Liverpool jersey.
Football Association rules prevent players from delivering personal messages in English top-flight competition.
However, given the exceptional circumstances, the Daily Mail reports that Diaz will not face any action on this occasion.
Emotion understandably spilled out of the South American as he continues to face challenges on and off the field.
Diaz’s parents were abducted at gunpoint in his homeland by the anti-government ELN group.
His mother has been rescued, but his father remains missing after being taken from a petrol station on October 28.
The rebel group holding Luis Manuel Diaz have vowed to release him “as soon as possible”, with peace talks having taken place across a number of days.