Ghanaian midfielder Moussa Narry's deflected shot in the 85th minute gave Sahel the victory and a berth in Wednesday's semifinals against Boca Juniors.
"I'm happy we survived," Etoile's French coach, Bertrand Marchand, said. "Pachuca is a better team than us and has more experience. We're looking forward to Boca -- and then AC Milan."
Pachuca, Mexico's oldest club, finishes the 2007 season with three titles -- CONCACAF Champions Cup, Mexican Clausura and SuperLiga.
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