The incident happened during the first-half of Reading's 2-1 Capital One Cup win at Fratton Park last night and was immediately reported by Blackman to referee Gavin Ward.
Now the Football Association have confirmed they've written to both Portsmouth and Reading to ask for their observations on the incident.
The Daily Mail are carrying the quotes of one Portsmouth fan who claims that 'monkey gestures' were made towards Blackman by a fan in the home end, though at this stage those reports haven't been confirmed by either club or the FA.
Speaking after the game, Reading assistant manager Kevin Keen told Get Reading.
"For that to happen to Nick and for him to come through and respond in the right manner by scoring a goal that puts us on the way to a good win, shows you what sort a person he is.
"So massive credit to him."
Sadly this wouldn't be the first time a Reading player has been subjected to racist abuse recently, with Garath McCleary being racially abused during the 3-0 FA Cup win over Bradford back in March.
Reading have now released a statement on the incident stating....
Reading Football Club can confirm that the Football Association contacted us this morning requesting our comments and observations regarding an incident in the crowd at Fratton Park last night.
The incident was immediately reported to referee Gavin Ward by Royals forward Nick Blackman during the first half of yesterday evening's Capital One Cup win over Portsmouth. The club will now liaise further with the FA and offer the relevant authorities all the help we can provide on this matter.