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ATLANTA — Funny how fast perceptions can change in the NFL. Nine days ago, the Buffalo Bills were undefeated, a dead-bang lock for the No. 1 seed in the AFC and ready to charge through that still-open Super Bowl window. Two games ago, the Falcons were left for dead after losing 30-0 to the lowly-at-the-time Carolina Panthers.

Now, after a 24-14 Atlanta victory, the Bills are looking surprisingly vulnerable, and the Falcons are looking surprisingly solid. These perceptions, too, might not hold, but for now, Atlanta looks like a team on the rise, and Buffalo like a team facing unexpected questions. 

Coming into the game, the Bills were still looking to repair the damage from losing their pristine undefeated record last week at the hands of the Patriots. The Falcons, coming off a bye, needed to prove to the league, their fans and probably themselves that they weren’t just the same-old, same-old underachievers.

And they would need to do it in front of a massive, and loud, contingent of Bills fans. Atlanta is always a destination for traveling fanbases from Pittsburgh to Dallas — the city is easy to reach by air, and the team is often, shall we say, accommodating to its visiting opponents.

First half: A pair of Falcons highlights

The Falcons, who haven’t reached the playoffs since the 2017 season, played one of their finest halves in years to start the game. Both teams scored on their opening drives, but only Atlanta could keep the momentum going with two more highlight-level touchdown drives. First, Bijan Robinson unleashed the longest run of his career, an 81-yard sprint along the sideline that put Atlanta up 14-7:

Next, Drake London caught a Michael Penix Jr. pass just shy of the end zone, and reeeeeached out to break the plane:

London came within a footstep of a second touchdown on the final play of the first half, stepping out of bounds while diving for the pylon. Even so, Atlanta took a 21-7 lead into the locker room at halftime, and the many Bills fans under the open roof of Mercedes-Benz Stadium were a whole lot more nervous than they thought they’d be.

Second half: Missed Buffalo opportunities

Allen led Buffalo on another touchdown drive coming out of the locker room, but he was pressured all night, the Falcons establishing a harassing defense they’ve lacked for years. Buffalo went three-and-out four times, Allen again and again unable to break contain.

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After Monday night, it’s clear that neither of these two teams is who we thought they were. The Bills remain a very good team, certainly one of the best in the league, but with some visible and exploitable flaws. Atlanta, meanwhile, has managed to find a new gear, as evidenced by their contained, controlled final drive that bled out all three of Buffalo's timeouts, and soon afterward, a game-ending interception, the second of the night for Allen. 

What's next: Building on, learning from Monday night

The Falcons now travel to face San Francisco before meeting two more AFC East opponents in Miami and New England. Buffalo, meanwhile, gets a week off before facing the Panthers, followed by yet another marquee matchup with the Chiefs to start November. Both teams learned a few lessons Monday night; it'll be on each of them to turn that knowledge into victories in the coming weeks.