With 40 seconds to play on Saturday, St. Louis outside linebacker Chris Garrett blocked a punt by Birmingham’s Drue Chrisman to give the Battlehawks the football at the Stallions 47-yard line trailing by four points.

That set the stage for the kind of comeback victory that St. Louis quarterback AJ McCarron has become accustomed to delivering since joining the Battlehawks last season.

And adding electricity to the storyline was the United Football League game’s location – Protective Stadium in Birmingham. A former All-American and national-championship quarterback at Alabama, McCarron also was a prep star at St. Paul’s Episcopal in Mobile, and Saturday’s United Football League game was his first action in his home state since the Kick Six Iron Bowl in 2013.

But about seven minutes of game time before the blocked punt, McCarron had walked to the sideline and told the St. Louis coaches: “Hey, my ankle’s broken.”

Despite his injury proclamation, McCarron did not miss a snap. But he couldn’t deliver the dramatic game-winning drive either as Birmingham stayed undefeated 30-26 victory.

McCarron did not speak at St. Louis’ postgame press conference, as he usually does, as the Battlehawks said he was receiving treatment. Coach Anthony Becht did not provide an update on the quarterback during his postgame remarks.

“I know he wanted to deliver today,” Becht said, “and we just came up short. …

“He’s been doing it his whole life. He’s played in front of 100-plus thousand fans. He can deal with 10 or 12 (thousand), and most of them were cheering for him. That’s good, you know? I know he wanted this one. I know he wanted to bring this one home.”

McCarron’s return to Alabama was used as a marketing tool by the UFL, and with a reported attendance of 14,056, Birmingham had its biggest crowd of the season.

About two hours after the game ended, a statement from St. Louis said McCarron had sustained a left ankle injury and would undergo further evaluation.

McCarron had just completed a third-and-8 pass to wide receiver Hakeem Butler for a 15-yard gain to the Birmingham 22-yard line when he was taken down by Stallions nose tackle Carlos Davis on an incompletion.

Davis hit McCarron in the shins, then rolled the QB over holding his legs and got a roughing-the-passer penalty. St. Louis running back Jacob Saylors scored on a 7-yard run on the next snap to give the Battlehawks a 26-23 lead with 7:43 to play.

McCarron made his ankle announcement after the conversion try and went into the sideline medical tent.

After a 40-yard touchdown pass from quarterback Adrian Martinez to wide receiver Kelvin Austin Jr. allowed Birmingham to take a 4-point lead with 5:23 remaining, an 8-yard loss on a sack, an 8-yard run by Saylors and an incompletion on a long pass gave the Battlehawks their first three-and-out since the opening possession. St. Louis punted with 3:10 remaining.

But Garrett’s blocked punt gave the Battlehawks an opportunity to pin the first loss of the season on Birmingham. A 7-yard completion to Saylors was followed by a run for 1 gain by McCarron as the quarterback somehow eluded a sack. But with St. Louis out of timeouts, the next snap had to be a spike to stop the clock.

A fourth-down throw to wide receiver Jahcour Person was broken up by linebacker Kyahva Tezino with 11 seconds left to seal the Stallions’ victory.

McCarron finished the game 19-of-32 passing for 161 yards with one touchdown and one interception. He ran for 24 yards on two carries, and his scrambling allowed him to throw an 8-yard touchdown pass to Saylors as the Battlehawks took a 20-17 lead with 6:17 left in the third quarter.

The Battlehawks face the D.C. Defenders at 11 a.m. May 19 at the Dome at America’s Center in St. Louis. ABC will televise the game.

At 5-2, St. Louis will be at least tied for the XFL Conference lead after the United Football League’s Week 7 games are completed. But it remains to be seen if the Battlehawks will have their starting quarterback against D.C.