The first year of the Bryan Harsin era ended, fittingly, under grey skies in the Birmingham Bowl.

Auburn gave up a late touchdown to Houston and couldn’t muster enough offensively to end its season on a positive note. Instead, the Tigers dropped their fifth straight—and another in heartbreaking fashion—in the form of a 17-13 loss to the 20th-ranked Cougars.

Auburn erased an early double-digit deficit and staked its first lead late in the third quarter, going ahead 13-10. But the Tigers couldn’t hold on, with the Cougars answering with a go-ahead 26-yard touchdown pass from Clayton Tune to Jake Herslow with 3:27 to play. Auburn’s ensuing drive ended with a thud, as T.J. Finley’s fourth-down pass attempt to Kobe Hudson fell incomplete and the Tigers turned it over, never seeing the ball again.

It’s the first time Auburn has ended a season with five straight losses since 1950, when the program went 0-10 under Earl Brown, and it’s the program’s first losing season since going 3-9 in 2012.

Here are AL.com’s key takeaways from the Birmingham Bowl:

Auburn has questions to answer on offense heading into 2022, but two certainties

The Birmingham Bowl didn’t do much to answer some of the many questions Auburn’s offense will face this offseason, but there are two things clear for the Tigers on that side of the ball as the team turns the page to Year 2 of the Harsin era—they have two key weapons to build around offensively.

Tank Bigsby turned in another big day with an all-around performance out of the backfield. He finished with 88 rushing yards to pace the offense, and he also led the team with five receptions for 68 yards, including a 51-yarder in the first half. Getting him back for his junior season—he said last week that he did not consider transferring from the program since the regular season ended—will be huge for this offense as Harsin and new offensive coordinator Austin Davis try to turn things around on that side of the ball. The other certainty for the Tigers: They have a certified No. 1 receiver heading into 2022 with Kobe Hudson, who closed the season strong with four receptions for 57 yards and the go-ahead touchdown in the third quarter. Hudson finished his sophomore campaign with 44 catches for 580 yards and four scores, and he should head into next year as the Tigers’ top target in the passing game.

The offense still faces plenty of questions, though, namely at quarterback. T.J. Finley had his first true audition for the starting job, but he turned in an uneven performance against Houston. He completed 19-of-34 for 227 yards and a touchdown. To his credit, he was sharp on the go-ahead scoring drive in the third, completing 5-of-5 passes for 82 yards and the touchdown to Hudson, but he couldn’t help Auburn answer the late score by Houston.

Auburn’s offensive line will also need to be reconfigured, as the team will lose Brodarious Hamm and will potentially have to replace seniors Nick Brahms, Brandon Council, Austin Troxell and Alec Jackson, barring any of them taking advantage of their free year of eligibility. The Tigers will also likely have to replace the production of senior tight end John Samuel Shenker, who capped the most productive season by a tight end in Auburn history. On Tuesday he broke the program’s single-season record for receptions and receiving yards by a tight end.

Defense stepped up without its two best players, but it wasn’t enough

Down All-America cornerback Roger McCreary and All-SEC linebacker/leading tackler Zakoby McClain, Auburn’s defense came up big in the Birmingham Bowl, navigating a slow start and riding it into a formidable effort to close out the season.

The Tigers gave up a long touchdown drive to the Cougars on the game’s opening possession, missing a couple of opportunities to get off the field before Clayton Tune found Alton McCaskill to cap an 87-yard scoring drive. It was a less-than-ideal start for Auburn’s defense, but the unit didn’t let the early score define its final game of the year, turning in a strong showing until Houston’s go-ahead drive in the fourth—when Auburn was down two more starters in the secondary, with Smoke Monday and Jaylin Simpson both ejected for targeting.

Between the early touchdown and the go-ahead score late, Auburn allowed just three points over the next nine drives, forcing four punts, snagging a pair of interceptions and getting a key fourth-down stop early in the fourth quarter. After that early touchdown drive, the Tigers didn’t allow another third-down conversion until early in the fourth quarter — a period that spanned eight Cougars possessions.

It was a particularly inspired effort from the likes of senior Chandler Wooten, who led the team with 11 tackles, including that aforementioned fourth-down stop, and picked off a trick play attempt on Houston’s following drive; and Smoke Monday, who had five tackles, including one for a loss, before being ejected in the third quarter for targeting.

Credit to Ben Patton

Auburn’s special teams were dealt a blow last month when Anders Carlson sustained a season-ending ACL injury that required surgery. Carlson’s injury thrusted walk-on Ben Patton into the spotlight for Auburn in that phase of the game—no easy ask—and the Rochester, Mich., native delivered.

Patton was 2-of-2 on field goals against Houston, with makes from 27 and 35 yards for Auburn’s first two scores of the game. He entered the game 3-of-4 on field goal tries over the prior two games and finished the season 5-of-6.

AL.com will update this post.

Tom Green is an Auburn beat reporter for Alabama Media Group. Follow him on Twitter @Tomas_Verde.