In AAF debut, Christian Hackenberg showed why he never played in NFL

Christian Hackenberg of the New York Jets warms up before the game against the New England Patriots at Gillette Stadium on Dec. 31, 2017 in Foxboro, Mass. 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’ 26-0 loss to the Birmingham Iron. With about four…