ATLANTA — A fourth-quarter comeback fell short for the Atlanta Falcons in their Week 1 game against the Tampa Bay Buccaneers at Mercedes-Benz Stadium.

Final score: Buccaneers 23, Falcons 20

Why it's important: The Falcons face an uphill battle from here, not only beginning their season 0-1 but also already dropping in the NFC South race with this loss to a divisional opponent.

Key takeaway: Jeff Ulbrich's defense came to play. The Falcons forced the Buccaneers into back-to-back three-and-outs to start the game. The last time the Falcons forced a three-and-out on the first two drives was in 2015 against the Philadelphia Eagles in a season opener Atlanta won. The Falcons' biggest task this offseason was revamping the defense, and Sunday showed they did just that. The unit has clearly embraced the newly implemented attack-style front because the players brought the energy.

Key moment: Trailing 17-13 with three minutes remaining, the Falcons offense lined up on fourth down at the Buccaneers' 2-yard line. Quarterback Michael Penix Jr. kept the ball, running and diving toward the left end-zone pylon. Initially, the play was ruled a fumble. But after further review, Penix was down before losing control and secured the first down needed. And four plays later, Penix finished the job with a 4-yard touchdown run. The Falcons took the lead, 20-17.

• More: That drive was crazy. It began at Atlanta's own 9-yard line, required two fourth-down conversions and consisted of 18 plays total. Wide receiver Drake London had what appeared to be a touchdown catch before Penix's final run, but it remained incomplete after a Falcons challenge.
• The 18-play drive signified the Falcons' most plays on a single offensive drive since a 20-play drive against the Green Bay Packers on Oct. 5, 2020. It tied for the Falcons' most plays on a touchdown drive since Dec. 12, 2010 against the Carolina Panthers.

The craziness didn't end there. Because the Buccaneers answered within a minute's worth of time. A 25-yard touchdown pass from quarterback Baker Mayfield to wide receiver Emeka Egbuka capped off a quick five-play, 63-yard scoring drive to put Tampa Bay back in charge. The Buccaneers, though, missed their point-after attempt, so they were up by only three points rather than four.

The Falcons then had a minute of their own to work their magic. They set kicker Younghoe Koo up for a 44-yard field goal that would trigger overtime. But he missed.

Standout performance: Divine Deablo. The inside linebacker, donning the No. 0 for the Falcons, was all over the field in his first game. All offseason and preseason, the Falcons' coaching staff praised Deablo’s stature and athleticism. Those qualities and so much more were on display Sunday. He finished with six tackles, a half-sack, and a pass breakup.

Number to know: 4. All four of the Falcons' defensive draft picks made their debuts. Safety Xavier Watts and cornerback Billy Bowman Jr. started, while edge rusher Jalon Walker and James Pearce Jr. came off the bench. This shouldn't have been a surprising, considering Falcons head coach Raheem Morris said as much would happen last week, but still good to see an early return on investment in Atlanta.

Player milestone:

• Wide receiver Casey Washington got his first career start. His 19-yard reception in the first quarter then marked the longest of his career. He had just one catch for 14 yards as a rookie.
• Cornerback Billy Bowman Jr. got his first career start. In the second quarter, he took down quarterback Baker Mayfield — with help from edge rusher Divine Deablo — for the rookie's and the defense's first sack of the season. Bowman makes for the 10th Falcons rookie to record a sack in his NFL debut. None have ever had more than one sack.
• Safety Xavier Watts got his first career start. In the third quarter, he became the third Falcons rookie with at least two passes defensed in his NFL debut over the last 35 years, joining cornerback Robert Alford (two in 2023 and defensive back Anthony Phillips (two in 1994).
• Running back Bijan Robinson had a 50-yard touchdown reception on the Falcons' first drive. It was his second career receiving touchdown of at least 50 yards, which ties for most by a Falcons running back. The others on that list are Williams Andrews, Antone Smith and Harmon Wages.
• That 50-yard touchdown pass is the longest completion of quarterback Michael Penix Jr.'s career so far.

Injury updates:

• Wide receiver and return specialist Jamal Agnew was deemed questionable early in the third quarter due to a groin injury. He did not return.
• Wide receiver Drake London injured his shoulder late in the fourth quarter and was questionable to return. He did not.

A quick tweet: The Falcons editorial staff of Tori McElhaney, Will McFadden and Terrin Waack share their gut reactions to Sunday's outcome in 280 characters or less.

• McElhaney: Michael Penix Jr. said this preseason that the Falcons have the potential to be the greatest offense in the league. They have a long way to go to make that proclamation a reality.

• McFadden: The Falcons showed flashes of what they can become, especially on defense, but there is work left to do.

• Waack: IT'S ONLY WEEK 1.

Setting the storylines:

• The biggest question entering Sunday was whether Falcons wide receiver Darnell Mooney would be active. The answer came with the inactives. It appears he has not fully recovered from the shoulder injury he sustained in the first practice of training camp.
• Elijah Wilkinson did indeed get the start at right tackle. It marked his 46th career start and his 10th with the Falcons. That experience helped Wilkinson carry confidence into his elevated role.
• Even before Week 1 began, Falcons head coach Raheem Morris named safety Xavier Watts and cornerback Billy Bowman Jr. starters. Those rookies, along with edge rushers Jalon Walker and James Pearce Jr., were expected to play substantial snaps against the Buccaneers – and here’s why Morris believed in his defensive draft class so much.
• Only four of the 14 NFL experts predicted the Falcons would win their opener. Look back on those receipts now that the game is over.
• Recap all of the news leading up to Sunday’s game in one spot.

Looking forward: The Falcons hit the road in Week 2 to face the Minnesota Vikings next Sunday, Sept. 14. Kickoff is scheduled for 8:20 p.m. ET at U.S. Bank Stadium. NBC will carry live-game coverage.