Blue is D, Red is O.
Blue runs down and sets up in the 1-3-3.
1 is taking away the around throw, as well as making sure the IO is contested and must come from an area that 2 can cover. 2 is covering the IO, as well as low throws to the area on the weak side in front of 6. 3 is deep than the rest of the front line, and has their hips facing sideways such that they are looking at the sideline. Their head is on a swivel and is finding where the players are positioned down field so that they can defend accordingly. It is this aspect that differentiates the 1-3-3 from a four-man cup. 4, who will generally be a tall athlete, is guarding some of the hole between 4 and 3, and also watching for any OI throw up the field to 7.
As the disc is swung to the sideline, 1 shifts their mark to take away the dump. 2 prevents the pass straight back across to 3, and 3 has dropped off more to take away some of the floaty passes back into the gap in the middle. 4 is busting to the sideline to take away the up line throw to 7, and then as 5 fills in they are shifting back towards the middle a little bit. 5 and 6 are now entirely on hammer watch. 7 is poaching in as much as possible, without losing either 6 or 7.
As a hammer is thrown to the other side the zone shifts as a unit to cover the up field throws. The members of the cup are all running on a horizontal line back to their position to cut down the angle on any up the field throws. 1 is busting back to reestablish the force. 2 is getting over on the IO and then re positioning towards the middle of the field because the IO is less of a threat on this sideline. 4 is coming over and preventing any reverse field throw that come back against the grain as the rest of the D is moving. 3 is the last member of the cup to set, as they have dropped significantly and are taking away the initial receivers. Since the hammer should take a while to come down, 3 has time to get out into the down field area and take away those throws. Only once the rest of the D is set does 3 sink back into the cup. Since most offensive players will be rushing forward for the next continuation up field, 6 must take away the immediate up line throw, 5 must take away the continue up the middle, and 7 can come in to take away anything behind them.
The defenders re position themselves and wait for the next swing.
As the disc swings all the way around the defenders run as a unit and thus take away any throws up field thru any gap that opens up when two players are not in sync.
If 2 dumps directly back to 1, 2 flashes out into the swing lane, and 1 makes their mark big to prevent the IO throw across to 3. 3 on D then compensates down, and 4 exposes the sideline slightly to cover for 3.
Then, as 1 adjusts their mark to take away the around, 2 rejoins the D, 3 and 4 re position, and 5 drops off a bit more.
Hopefully we can force a miss throw or a D after trapping them on the sideline. The power of this zone is on the sidelines and in preventing throws thru the cup. Hopefully we can force them to throw multiple over the top throws before they can score, in which case we should get it.