Click two points on the pitch to draw a temporary arrow, then specify event details and click 'Add to Pitch'. Your temporary line will be replaced with a chalk one.

You can add as many lines as you like.

'Player Position' and 'Opponent Position' are represented by single points drawn at the line's origin.

Delete a line by double clicking on its origin.

You don't have to label every mark. If the board is getting cluttered, you can use un-labelled points for opposition players etc.

The chalkboard works on mobile too! (Although you might not be able to double click to delete points). Why not try it live from a game?