The two-alarm fire was reported at 12:37 a.m. at an apartment in the 200 block of Robert Street, a fire dispatcher said.
Firefighters rescued the man, who accidentally sparked the fire when he discarded a cigarette into a paper wastebasket next to a chair he then fallen asleep in, Fire Marshal Lewis Broschard said.
The victim was taken to a hospital to be treated for injuries that were considered life-threatening as of this morning, Broschard said.
The blaze was eventually extinguished at 1:08 a.m., the dispatcher said.
Broschard said the fire caused an estimated $30,000 in damage to the apartment.