Mettenberger completed 16-of-19 pass attempts, picking up 282 yards and throwing three scoring strikes to Odell Beckham for the Tigers (2-0).
Jarvis Landry hauled down five passes for 71 yards and two scores. Beckham finished with five grabs for 136 yards.
UAB (0-2) was led by Austin Brown, who was held to 9-of-24 efficiency for 136 yards with a touchdown.
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