What is the ruling on playing football in a field adjacent to a graveyard, and is it considered a violation of its sanctity if the ball could fall inside the graveyard?

Graves hold great sanctity and must be respected. The Prophet, peace and blessings be upon him, forbade walking with sandals between graves and sitting upon them. Playing ball near graves, and the resulting entry of players into them to retrieve the ball, is a violation of their sanctity. Therefore, this should be avoided.