South Yorkshire police will investigate complaints about Sheffield United goalkeeper Paddy Kenny's behaviour after their 3-2 victory over Hull.
Some Hull fans complained about Kenny's behaviour
David Unsworth's late goal earned a win which boosted United's promotion hopes.
"Complaints have been received from Hull fans that the goalkeeper made gestures," said a police statement.
The Football Association said it would wait to hear from the police before taking any possible action, and that any police inquiries took priority.
Superintendent Martin Hemingway, head of the Sheffield Football, Events and Licensing Unit, added: "A number of complaints have been received and officers are looking into them.
"We need to get a full picture of what is alleged and gather the available evidence.
"There is no doubt that events on the field affect the behaviour of spectators and allegations of deliberate taunting are always taken very seriously."
Saturday's Yorkshire derby attracted a crowd of 26, 342, and five arrests were made.