Praise be to Allah.
There is nothing wrong with your praying in this place. The events that happen there (sports) do not mean that the Eid prayers and prayers for rain cannot be held there, so long as it is clean and pure (taahir) and there are no impurities (najaasah) present. If you can find a better place of your own, that would be preferable. And Allaah is the Source of strength.