Chile striker Humberto Suazo and Aldo de Nigris scored in a four-minute spell in the first half to put Monterrey 2-0 ahead before Carlos Esquivel replied for the Red Devils with a long-range effort one minute before the break.
Suazo's compatriot Hector Mancilla, controversially overlooked by Chile coach Marcelo Bielsa, levelled on the hour with his seventh goal of the championship.
Suazo put Monterrey back in front with a 70th minute penalty, equalling Mancilla's tally of seven goals, but Sergio Santana levelled three minutes later.
Toluca lead Group Three with 16 points from eight games.
Group One leaders Pachuca lost the championship's only other unbeaten record when they were thumped 5-0 at Guadalajara who scored all their goals in the second half.
Aaron Galindo headed the first one minute after the restart, striker Omar Arellano scored twice and Gonzalo Pineda and Hector Reynoso each converted a penalty to complete the rout.
Pachuca had Javier Munoz sent off for a second bookable offence in the 83rd minute.
The win took Guadalajara, the only team not to field foreigners, top of Group Two with 12 points while Pachuca lead Group One with 17.
The 18 teams play each other once in the qualifying stage but are divided into three groups.
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