In Figure 1 there are three merged states: 30 − 30/deuce, 40 − 30/A1 and 30 − 40/A2.
They represent the recurring situation when the players have both scored the same number
of points (deuce) and now need a two-point advantage to win. Subsequently, whenever the
player has a one-point advantage this is marked through state A1 and when her opponent
has a one-point advantage this is marked through state A2.