Darlington lost 1-0 at Edgar Street in August |
Midweek, as reported by The Northern Echo, Armstong said his side were going to get better and better with only five points from six games. They failed to get anything at Edgar Street in August, with Hereford nicking a 1-0 win.
But after a woeful 5-0 defeat at Buxton, they're now 23rd in the National League North.
Armstong was missing from the game.
It's not clear why, but the club said it was for "personal reasons".
Darlington fans, furious with the defeat and the club's poor start to the season, vented on social media. Some are even calling for Armstrong to be sacked, despite Darlo finishing 10th last season under his leadership.
It was, after all, a close season, with just five points separating Brackley Town in fourth and Curzon Ashton in 13th.
Alan Tibbir Robson said: "I don't know what is wrong with these players. Not an ounce of commitment shown.
"One of their players was taunting the Darlo fans about how crap we were. It didn't work, we agreed! No one wanted it today.
"They went through the motions to pick up their wages. Not acceptable does not even come close."
John Emerson said: "Southport were bottom of the league before today's game sacked manager after six games, brought Jim Bentley as manager won away today with the same players that had failed to win.
"Need I say more? Whatever the case AA [Alun Armstrong] has to go especially if the rumours say he did not attend the game."
Damian Robinson: "Do the decent thing and walk away. You are killing our club."
Meanwhile, his son Luke's transfer from Harrogate to fellow League Two side Wrexham has seemingly fallen through.
This summer, after the club had rejected transfer bids for him, Armstrong, who's on a deal until 2025, made himself unavailable for selection.
On the final day of the transfer window, Wrexham agreed terms with Harrogate to sign Armstrong but it wasn't completed by the 11pm deadline.
In a club statement, Wrexham said the "required documentation and clearance requests could not be completed in time and Armstrong's registration has been rejected".