Arsenal were forced to deal with a mouse infestation at the Emirates - spreading across all four levels of the stadium.
A hygiene report found that there was "extensive evidence" of issues around the stadium, dated in October 2016, with mouse droppings found in a host of different places.
Inspectors reportedly found evidence in kitchen areas, including behind ovens, under pipes and in pot wash areas used by catering staff.
Staff members were unaware of the issue before the report, with inspectors having to use torches to point out the situation to them.
Arsenal insist that they have now dealt with the issue, which was flagged late last year, and remain in a working relationship with external companies.
The report claims that mouse droppings were found in The Diamond Club Kitchen, Cox Kitchen 7 and The Woolwich Bar, among others, according to the Mail.
A lack of cleaning was cited as one of the main reasons for the problem, while further mouse proofing was required around the stadium to shut off the pests' access to water and food.
The report also claimed that they "must" check for mouse activity every time that they open and close the stadium, while also providing torches for staff members to help them to do so thoroughly.
An Arsenal spokesman told the Mail: "The health, safety and security of our fans is always our first priority and we were therefore very disappointed to learn of these deficiencies in October 2016.
"Upon receiving the report, we immediately implemented a series of measures to address the areas of concern.
"We are confident in the steps we have taken in the last year and continue to work with external experts to ensure that we are taking the right actions moving forward."
The Emirates Stadium, where Arsenal have been based for 13 years, is next to the East Coast Main Line, which is thought to have been one of the contributing factors to the infestation.