The draw for the tournament took place on 22 December 2017. 27 teams were drawn into nine groups of three, with each group containing one team from each of the three pots. Clubs in Pot [|1] were drawn to be the seed of each group according to the order of their drawing. That is, the first club that was drawn is seed of Group 1, the second drawn is seed of Group [|2] and so on and so on. The Liga MX teams in Pot 1 are the four best teams in the Apertura 2017 classification table not participating in the 2018 CONCACAF Champions League as well as the defending champion. Due to the defending champion Monterrey already being one the four best teams in the Apertura 2017 classification table, León, who was the fifth best placed team in the table, was also drawn into Pot 1. Pot 1 also contained the top three Ascenso MX teams in the Apertura 2017 classification table Pot 2 contains the next four best Liga MX clubs in the Apertura 2017 classification table not participating in the 2018 CONCACAF Champions League. Pot 2 also contains the Ascenso MX clubs who ended 5–9 in the Apertura 2017 classification table. Pot [|3] contains the next five best Liga MX clubs in the Apertura 2017 classification table not participating in the 2018 CONCACAF Champions League. Pot 3 also contains the Ascenso MX clubs who ended 10–13 in the Apertura 2017 classification table.
Teams
Tiebreakers
If two or more clubs are equal on points on completion of the group matches, the following criteria are applied to determine the rankings:
scores of the group matches played among the clubs in question;
The clubs that advance to this stage will be ranked and seeded 1 to 16 based on performance in the [|group stage]. In case of ties, the same tiebreakers used to rank the runners-up will be used.
All rounds are played in a single game. If a game ends in a draw, it will proceed directly to a penalty shoot-out. The highest seeded club will host each match, regardless of which division each club belongs.
The winners of the groups and the seven best second place teams of each group will advance to the Knockout stage.
Qualified teams
The nine group winners and the seven best runners-up from the group stage qualify for the final stage.
Group
Winners
Runners-up
1
Tapachula
León
2
Oaxaca
—
3
Monterrey
—
4
Toluca
Santos Laguna
5
UNAM
BUAP
6
Zacatepec
Necaxa
7
Tampico Madero
Atlas
8
Celaya
Pachuca
9
Morelia
Querétaro
Seeding
Bracket
Round of 16
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Quarterfinals
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Semifinals
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Final
Top goalscorers
Players sorted first by goals scored, then by last name.
Alexis Canelo
Eduardo Pérez
Édgar Bárcenas
Carlos Sánchez