During a throw-in, A1 passes the ball over the braces supporting a rectangular backboard. The ball does not touch any of the braces and is subsequently controlled by A2, who throws the ball in Team A’s basket. The ball did not pass over any part of the rectangular backboard.
The ball was live and the throw-in ended when it was touched by A2, thus A2 scored a field goal. This play is somewhat different than those most frequently used to bring out the point that the ball becomes dead when it passes over a rectangular board. The rules do not identify the supports as being part of the backboard.