The team made the announcement about 90 minutes before kickoff Thursday.
Bortles has completed 28 of 45 passes for 435 yards and a touchdown in three preseason games, but coach Gus Bradley says Chad Henne will start the season opener at Philadelphia.
Henne will dress against Atlanta, but probably won't play.
Nine players won't dress for Jacksonville because of injuries: kicker Josh Scobee, safety Winston Guy, cornerback Alan Ball, safety Craig Loston, right tackle Austin Pasztor, guard Zane Beadles, offensive tackle Josh Wells, tight end Clay Harbor and defensive tackle Sen'Derrick Marks.
The Jaguars made several other changes to their lineup, most notably starting running back Denard Robinson.
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