M-drop

The M-drop is a play in the sport of water polo which is mainly used when there is a strong, offensive set of players. The defense sets up in an M-shape, hence the name "M-Drop".

A basic offense would look like an umbrella shape, with 5 offensive players in a half-circle around the goal, with one defensive player on each of them. There is one player in the middle, called set. There is one defensive player guarding each of the offensive players. From left to right, and moving around the circle, the offensive players are named 1, 2, 3, 4, 5, and the set is 6. The defensive players are named D1, D2, D3, D4, D5, and D6, who guard sets.

If the opposing team has a very strong set player, the D3 player will drop back and help the D6 player. This play leaves the D3 player open, so defensive members D2 and D4 will “split” while swimming in between their player and D3. They also split in between the set and their player, hence the name M -drop, from the ‘M’ shape created. :)

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Wikipedia