Christian Hackenberg practices while with the Eagles in 2018. (Matt Rourke/Associated Press)

The Alliance of American Football may have enjoyed a solid debut over the weekend, but it didn’t go so well for Christian Hackenberg. The former Penn State star and second-round pick of the New York Jets, who never played a regular season down in two-plus NFL seasons, struggled as his Memphis Express was shut out Sunday in its opener.

Hackenberg completed just 10 of 23 passes for 87 yards and an interception, plus he was sacked twice and flagged for intentional grounding, in Memphis’s 26-0 loss to the Birmingham Iron. With about four minutes left, he was lifted from the game in favor of backup quarterback Brandon Silvers, but not before Hackenberg left as big an impression with his potty mouth as he did with his spotty arm (warning: profanity)

“There’s three or four plays early I would love to have back,” Hackenberg said after the game. “We just never were able to string things together . . . It’s a good learning experience for us, and we’re going to keep fighting.”

If Hackenberg’s dismal performance was disappointing to him, it had to be for the AAF, as well, given that the 23-year-old is one of the league’s better-known players. That he never saw any meaningful playing time in the NFL added to intrigue about his debut, if only to answer the question: How bad could he be?

The Jets clearly felt that he had no business taking the field for them, despite having invested the 51st overall pick in the 2016 draft in him and not being blessed with an abundance of quarterbacking talent during his stay in New York. In Week 17 of his rookie season, the Jets kept him on the bench even though they had a 5-10 record and an injured starter in Bryce Petty, who took over in midseason for a thoroughly ineffective Ryan Fitzpatrick.

A similar scenario played out in the 2017 season’s finale, when New York was again 5-10 and had no compelling reason to see anything more from either Petty, who played poorly after replacing that season’s primary starter, 38-year-old Josh McCown. A few months later, the Jets used the third overall pick in the 2018 draft to take quarterback Sam Darnold, and they followed that by trading Hackenberg to the Raiders for a conditional seventh-round pick.

Oakland cut him a few weeks later, preferring to go with Connor Cook and EJ Manuel as the backups to Derek Carr, and Hackenberg went to brief stints with the Eagles and, once the 2018 season started, the Bengals’ practice squad. Cincinnati dropped him in November, and Hackenberg quickly latched on with the AAF, where he again went in the second round.

The former Big Ten freshman of the year said this week that he had offers to join other NFL teams’ practice squads, but he cast his lot with the fledgling league because he “needed to find a way to play.” Hackenberg was able to beat out Silvers, who played college ball at Troy, and former LSU Tiger and Tennessee Titan Zach Mettenberger for the starting nod, but his first foray into professional regular season action left much to be desired.

Hackenberg had said this week that he was pleased with his work on fixing his mechanics, including a long windup and poor footwork, but he added, “When you’re in a live game situation, you want to see how your body reacts; you want to see if you really did overcome those hitches or nuances or little hiccups that you wanted to try and erase.” On Sunday many of the flaws that dogged him coming out of college were still on display, including subpar accuracy and pocket awareness.

“He has to get better,” Express Coach Mike Singletary said of Hackenberg after the loss to Birmingham. “That’s the bottom line. I could sit here and talk about a number of things. But he just has to get better. Has to settle down, has to get better.”

Hackenberg had some moments Sunday, including a touchdown that was called back because of a penalty, but he certainly could have done better. At 6-foot-4, 228 pounds, he definitely looks the part of a professional quarterback, but whether he can play it, at any level, remains very much an open question.

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