One man was arrested and another served with a violence reduction order after an incident involving away fans at Sixfields on Saturday.
Northampton Town defeated Mansfield Town 1-0 in the first game of the 2014/15 season.
During the game, stewards and police had to deal with Mansfield fans damaging the advertising hoardings in the South Stand.
Pc Nick Price, county football officer for Northamptonshire Police, said a number of away fans were questioned after the incident.
“One male was arrested, one male was reported for a public order offence and one male was issued with a section 27 Violent Crime Reduction notice. Thankfully no permanent damage to the advertising boards at the South stand,” he said, via his Twitter feed, @NorpolFootball.
““Unfortunately a small section of the Mansfield Town fans let the club down today.
“The issues raised in relation to stewarding and police action/tactics will be reviewed by the force football lead Supt Mick Stamper, who will also be speaking with the club safety officer about the events today and where we can improve.”
Pc Price said there was also an incident away from the ground “where males linked to both clubs were involved”.
“This incident is still under investigation. CCTV and officer Body Worn Video will be reviewed and CPS consulted in relation to possible further arrests.
“If any arrests are made from any of today’s events, dependant on the subjects previous convictions, etc, football banning orders may be applied for.”