The games will be played behind closed doors and will be one-leg knockouts rather than the usual two legs, CONCACAF said on Monday.
However, the quarterfinal first legs that had already been played will count and those second legs will be played as part of the December tournament.
"The football community across the region, and the fans of the remaining eight teams in particular, can look forward to an exciting centralized finale of the competition in December and the crowning of a regional club champion," CONCACAF president Victor Montagliani said in a statement.
There will be high-frequency COVID-19 testing in the bubble-like environment for the tournament, with no fans allowed into the games.
The second legs of the quarterfinals already started -- Olimpia vs. Montreal Impact, Atlanta United vs. Club America, Tigres vs. NYCFC -- will take place over Dec. 15 and 16, although the times and locations are yet to be announced. Honduran side Olimpia take a 2-1 lead from the first leg against Thierry Henry's Montreal, while Tigres are 1-0 up versus NYCFC and America thrashed Atlanta 3-0 in its first game.
The LAFC against Cruz Azul game will be a one-game shoot-out, as will the semifinals and final. The winner of America against Atlanta will face LAFC or Cruz Azul in the semifinal with Tigres/NYCFC to play Olimpia or Montreal. Both games will be on Dec. 19.
There will be no extra-time at the quarterfinal or semifinal stage, with games instead going straight to penalties, although there will be extra-time for the Dec. 22 final, should the teams be level after 90 minutes.
Monterrey is the current CONCACAF Champions League holder, with Mexican teams having won the last 14 editions of the region's club tournament.
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