After Liberty turned it over on downs in five plays to start the game, Cole Talley kicked a 26-yard field goal to give Army (8-3) a 3-0 lead. The Black Knights followed up defensively when Bo Nicolas-Paul intercepted Max Morgan.
On Army's ensuing drive, Anderson threw a 34-yard scoring pass to Braheam Murphy for a 10-0 advantage just before the end of the first quarter.
The Flames continued turning it over on downs doing so on their next two possessions which resulted in Buchanan scoring runs of 19 and 1 yards for a 24-0 lead. His 7-yard scoring run came with 6:45 left in the third for a 31-3 lead.
Malik Willis threw a 14-yard touchdown pass to Noah Frith for Liberty's first touchdown of the day with 4:35 left in the third, and then Willis ran it in from seven yards seconds before the third ended to cut the deficit to 31-16.
Willis threw for 305 yards for Liberty (7-5).
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