The Mad Ants shot 33.7 percent from the floor in a 107-80 loss at Springfield on Sunday.
It was the third-lowest point total of the season for the Ants (22-22), whose previous season-lows have been 69 against Canton and 78 against Erie.
The loss dropped the Ants to a game behind Sioux Falls (22-20) in the chase for the eighth and final NBA D-League playoff berth.
Fort Wayne trailed 29-17 after the first quarter and never caught up, as Springfield (16-25) led 54-46 at the half and 77-65 after the third period. The Ants managed only 15 points in the final quarter.
Tony Mitchell led the Ants with 19 points, and Ron Howard added 14, but the two combined to go 12 of 38 from the floor, as the Ants connected on 30 of 89 field goal attempts.
Brandon Wallace had a double-double with 12 points and 12 rebounds.
The team also had 20 turnovers against 11 assists.
Forward Willie Reed led the Armor with 21 points and 20 rebounds.
Four other Springfield players reached double figures, with Paul Carter scoring 17 and Edwin Ubiles, 15.
Eight games remain in the Ants' regular season.
The Ants return to Memorial Coliseum for three games this week. They face Maine (22-21) on Thursday, Austin (23-18) on Friday, and Central Division-leading Rio Grande Valley (26-15) on Sunday.