A drop down list and a query on it.

Question

I am trying to create a drop-down list that is bounded with a datasource(SQL table).  there is a column name TeamID and TeamName in a table named team. in dropdown list as the user selects any team the data of that particular team is driven out from a table named "Players" where Team_ID is a foreign key. 

I am unable to resolve this query if any of you can help it would be really grateful.