Security and staff swept the ground to ensure the surface was safe before the session was able to go ahead.
Hawthorn CEO Stuart Fox said the Club acted swiftly to protect its players and supporters.
“When the objects were found, staff and security took immediate action to sweep the oval before the players took the field to ensure the surface was safe,” Fox said.
“We are fortunate no one was hurt, and I commend staff and security for acting quickly to protect our players and patrons,” he said.
