The Football Association have written to Hull City after an object was thrown at Sunderland defender Phil Bardsley during the clash at the KC Stadium on Saturday.
Bardsley had been fouled in an incident which led to Sam Ricketts getting a second yellow card from referee Mike Riley, then a plastic bottle from the crowd appeared to be thrown in the full-back's direction shortly afterwards as he prepared to take a free-kick.
Riley included the matter when he filed his referee's report to the FA.
"We are writing to Hull for their observations of the incident and what steps are being taken to identify the individual responsible," said an FA spokesperson.
Hull were eventually defeated 4-1 by Sunderland and defender Michael Turner is determined to bounce back against Manchester City on Boxing Day.
"We'll work hard as we always do when we've had a set-back," Turner said on hullcityafc.co.uk.
"We lost 5-0 to Wigan here and we bounced back very well from that. We'll work hard and get ready for Manchester City."
Turner has been linked with a move to City, but added: "My agent has had a couple of meetings with (manager) Phil Brown and hopefully in the next few weeks something can be agreed.
"We are looking to extend it and hopefully something can be agreed pretty quickly."