Five offensive players try to keep the ball away from two defenders. Switch defender with any offensive player who makes a mistake.
“Two players must show short for support”–player with the ball must always have two passing options nearby. These players should ‘open wide’ by getting to the sides of the grid quickly.
“Play facing the inside of the grid”–particularly when receiving a pass. Don’t get trapped in a corner.
“Communicate”–who’s pressuring the ball? Who’s in support?
“Don’t get split” — a split occurs when the ball is passed in between the defenders (as opposed to a pass to a supporting player on the side).
Vary the size of the grid.
Require a one or two-touch restriction.