Format

The Nitto ATP Finals has a round-robin format, with eight players/teams divided into two groups of four. The eight seeds are determined by the ATP Race To Turin and ATP Doubles Team Rankings on the Monday after the last ATP Tour tournament of the calendar year. All singles matches are the best of three tie-break sets, including the final. All doubles matches are two sets (no ad) and a Match Tie-break.

Draw

The top seeded players/team is placed in Group A and the second seeded player/team is placed in Group B. Players/teams seeded 3 and 4, 5 and 6, 7 and 8, are then drawn in pairs with the first drawn placed in Group A. Each player/team plays the three other players/teams in his group. The winner of each group (best overall record) is placed in separate semi-final brackets, with the top player/team in Group A playing the runner-up in Group B, and vice versa. If two or more players/teams are tied after the round robin matches, the ties are broken by the Tie-Break Procedure.

Semi-final Qualifying Procedure

The final standings of each group is determined by the first of the following methods that apply:
a) Greatest number of wins;
b) Greatest number of matches played;
    Comment: 2-1 won-loss record beats a 2-0 won-loss record; a 1-2 record beats a 1-0 record.
c) Head-to-head results if only two (2) players are tied,
d) If three (3) players are tied,
If three (3) players each have one (1) win, a player having played less than all three (3) matches is automatically eliminated and the player advancing to the single elimination competition is the winner of the match-up of the two (2) players tied with 1-2 records; or
Highest percentage of sets won; or
Highest percentage of games won; or
The player positions on the ATP Rankings as of the Monday after the last ATP Tour tournament of the calendar year.
If (i), (ii), (iii) or (iv) produce one (1) superior player (first place), or one (1) inferior player (third place), and the two (2) remaining players are tied, the tie between those two (2) players shall be broken by head-to-head record.

Comment 1: 1 player has 3 wins and the other 3 players have 1 win. Of the 3 players with 1 win, 1 player has only played in 2 matches while the other 2 players have played 3 matches. The player who has only played 2 matches is eliminated and then the 2 remaining players revert back to head-to-head results with the winner of their match advancing to the semi-finals.

Comment 2: 1 player has 3 wins and the other 3 players have 1 win and they all have played 3 matches.
The tie-break for % of sets won has 1 player with a better % than the other two. This player advances to the semi-final round.

Comment 3: 3 players have 2 wins and the other player has 0 wins. The player with 0 wins is eliminated. Of the 3 players with 2 wins, they are ordered by their % of sets won. This produces a 1, 2 & 3 order and the players finishing 1 and 2 move to the semi-final round and the player finishing 3 in % of sets won is eliminated. The player with the best % of sets won is the winner of the group.

Comment 4: 3 players have 2 wins and the other player has 0 wins. The player with 0 wins is eliminated. Of the 3 players with 2 wins, 1 player’s sets won-loss is 5-2 for 71.43%; the other 2 players both have a 4-3 record in sets for 57.14%. In this case there is 1 superior player (71.43%) and the remaining 2 players are tied; it now reverts to the head to head result of the 2 remaining players with the winning player advancing as group runner-up.

Comment 5: 3 players have 2 wins and the other player has 0 wins. The player with 0 wins is eliminated. Of the 3 players with 2 wins, 2 have set won-loss records of 5-3 (62.5%) while the other player is 4-3 (57.14%). In this case we have 1 inferior player (57.14%) and he is eliminated. The remaining two players both advance to the semi-finals with the winner of their head-to-head match advancing as the group winner.