The video speaks more than the words. What is special about drills that defenders will have to organize or re organize twice every time. Once protecting the first goal keeper and the second time the second goal keeper.
Please note that these drills are general and not team specific. What I mean to say that every coach must have the ability to rin the drills the way best for his team and players. If you find your defenders while possession the ball and in attack, if you find they lose the ball easily, you might add another line of players responsible for attacks. Another suggestion would be adding one more player, could be neutral, to the team while on attack giving them more chance to hold the ball. These drills meant to focus on defenders and they must be devised to assure so.
THE FOUR CORNERSTechnical/Tactical: