The Saints, who played for the NFC title last season, had 373 yards of total offense but only one touchdown.
Drew Brees completed 12 of 14 passes for 118 yards for the Saints.
J.P. Losman started for Buffalo, but the Bills picked up just one first down in his two series of work.
Three of the four NFL exhibition games played Friday night ended with a 13-10 score.
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