Johnnie Jackson admitted Gateshead looked like they wanted to reach the second round of the FA Cup more than AFC Wimbledon following his side’s shock 2-0 defeat.
The visitors were 1-0 up at half-time after Kain Adom finished off a superb move on the break in the 21st minute.
It was 2-0 five minutes into the second half when Fenton John turned the ball into the top-left corner from the centre of the penalty area.
Jackson said: “The performance, to be honest, was nowhere near what I expected from the group.
“That is what is frustrating for me, I can handle losing a game of football but not really in that way.
“We did not show up at all, it just looked like going through in the cup mattered more to them. It did not matter enough to us.
“We fight for every ball, I don’t think we did that today, I have to be honest. That has been a hallmark of my team. To see that missing hurts me.”
Gateshead manager Alun Armstrong revealed a difficult summer for the club made victory all the sweeter after full-time.
“It is huge, I don’t think people understand what this club went through in the summer,” he added.
“There was a massive turnover, saying we are running on a skeleton staff is probably an understatement.
“There is four members of staff running the football side of things at this moment in time, and that is it.
“I am so pleased for the fans because they have been through the mill in the summer and you heard them, they never shut up from the first minute.
“It would be nice to be on their bus on the way home, I know what they are like, me being from the area myself.
“I know exactly what that bus is going to be like; it is going to be a messy one.”
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