Prior to kick-off, there had already been a furor surrounding the fixture due to United captain Patrice Evra’s return to Anfield for the first time since Luis Suarez was handed an eight-game suspension for racially abusing the Frenchman in October.
While Evra was jeered by sections of the crowd, the game passed largely without incident, as Dirk Kuyt’s late strike ensured Kenny Dalglish’s side progressed to the fifth round of the Cup.
However, Merseyside Police have since confirmed to Goal.com that an alleged incident of racism from a supporter is “under consideration for investigation”.
The allegation comes as the Reds cap off a fine week on the domestic cup front, having reached the League Cup final on Wednesday at the expense of Manchester City.
The Police were also quick to stress that this was an isolated incident, with the vast majority of both Liverpool and United fans well-behaved throughout the clash.
Earlier this month, a Liverpool fan was arrested for making racially motivated comments towards Oldham Athletic’s 20-year-old full back Tom Adeyemi during the two sides’ third-round FA Cup clash, with the youngster making a full statement to the police.
Saturday’s incident follows on from the FA’s decision to cancel the pre-game handshake between QPR and Chelsea at Loftus Road, with concerns that Anton Ferdinand may snub John Terry over the race row surrounding the pair, and in turn provoke ill-feeling amongst the crowd.