Monterrey won the CONCACAF Champions League crown on Wednesday, falling 2-1 at Santos in the second leg of the final but emerging with a 3-2 aggregate victory in the regional club championship.
Neri Cardozo's goal in the 82nd minute, from a pass from second-half substitute Walter Ayovi, was enough to give Monterrey the aggregate victory after the second-leg contest in Torreon in northern Mexico.
Monterrey had triumphed 2-0 at home in the first leg last week to gain control of the tie for the North and Central America and Caribbean club crown.
Monterrey became the first club to win successive CONCACAF confederation titles since Pachuca in 2007 and 2008 and secured their berth in the FIFA Club World Cup Japan 2012.
They had to make do without Chilean striker Humberto Suazo, who scored both first-leg goals but was suspended due to an accumulation of yellow cards.
Argentinian Daniel Luduena, in first-half injury-time, and Oribe Peralta in the 51st minute had given Santos a 2-0 lead.
Monterrey beat Major League Soccer's Real Salt Lake 3-2 on aggregate in last year's final.