A common defensive play in polo is called "hooking". A player may hook an opponent by using their mallet to block an opponent's mallet while the opponent tries to hit the ball. Sometimes it is unsafe for a player to hook their opponent. As an example, reaching over or under the opponent's horse to make a hook is considered unsafe. An unsafe hook will cause the player to foul. If a player cannot safely hook their opponent, they may instead use a different defensive play called a "ride-off". A "ride-off" happens when a player uses their horse to push an opponent's horse away from the "line". This makes it difficult for the opponent to make a play on the ball. If the player crosses the line while trying to ride off their opponent, they will receive a foul.