The Jets had hoped Christian Hackenberg would show marked improvement in his second NFL season, but after an opportunity to win the starting job, the former Penn State quarterback has fallen to third string.

The Jets released their first depth chart before the regular-season opener against the Bills on Sunday, and Hackenberg is behind third-year quarterback Bryce Petty, who is listed as the backup to starter Josh McCown.

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Hackenberg started the Jets’ second and third preseason game so coaches could get a look at him with the first-team offense. But he had two poor outings against the Lions and Giants. Petty played well in the second half of both those of games but suffered a knee injury against the Giants. He missed the final preseason game against the Eagles but resumed practice this week.

The Jets also finalized their offensive line, naming Brandon Shell as the right tackle and Kelvin Beachum as the left tackle. Wesley Johnson is the starting center.