Stoke said they would hold an investigation into the incident, which occurred after Pulis told his players he expected them to train on Monday despite having previously agreed to give them the day off to attend a Christmas party.
Visiting manager Tony Pulis will rue his side's failure to hold onto their lead and Stoke have now thrown away 11 points from winning positions this season - but Hull were good value for their only their fourth league win of 2009.