salaam Its really good to see sania wearing hijab. see now no one says that she's hot or bla bla ....why....its because of hijab.....this is the miodesty gievn by Allah to every women but only if she maintains it. but it will be really good for her if she wears it every time but when she plays its better for her to cover her body as much as she can. If she is unable to do that then its a sin but for that she should pray to Allah from her Heart and ask for forgiveness as Allah is the best who forrgives his slaves