Alex Neil admits Sunderland 'shot themselves in the foot' and by giving the ball away and were punished by MK Dons, as his first home game in charge ended in defeat.
The Black Cats lost 2-1 at the Stadium of Light against play-off rivals MK, and for Sunderland it was their fourth defeat in five games, meaning they have now won just one of their last nine, and as a result they slipped out of the top six.
Sunderland were the architects of their own downfall against MK, giving the ball in midfield which allowed the visitors to score on the counter-attack twice in the second half.
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Sunderland have collected one point from Neil's first two games in charge and he knows he will have to address the problems quickly if they are to finish in the play-offs - let alone win promotion via that route.
"My overwhelming emotion is frustration," he said following the game.
"The first half was probably even, because they started quite brightly but we grew into the game, and just before half-time we were the better team, so 50-50 overall.
"Then in the second half we were the better side and we penned them in.
"But we risked the ball in central areas, and we got counter-attacked on twice and lost the game off the back of it.
"That's the biggest frustration. Our defensive structure when we were attacking was disappointing for both goals.
"But equally, we gave the ball away cheaply under little or no pressure.
"In terms of structure, strategy, and tactics - all that stuff - we got the majority of that right.
"We just made some silly errors that have cost us the match.
"Once we got the equaliser in the second half, I felt confident that if anyone was going to win the game it would have been us but ultimately we just made a bad decision and shot ourselves in the foot."
In the midst of such a dismal run, it was no surprise that the fans' frustration was also evident - although they continued to back their team until the final whistle - and Neil accepts that the bad decisions from his players made matters worse.
He said: "When we make a bad decision, when something goes against us, we don't react well.
"That's the first thing I see.
"Then we try to over-complicate it, we take too many touches, we run into areas we shouldn't, we don't move the ball quick enough and that's what I saw towards the end of the game.
"Some of the bits after the scored the [second] goal, when naturally the fans are frustrated, we made bad decisions.
"What we needed to do was simplify it, pass the ball forward, and get the fans back onside and try to build from there.
"Instead, if anything, we added to the frustration.
"This was my first game here [in charge at the Stadium of Light] and it's not even a case of not knowing what is expected - I do know that.
"What I said to them at half-time is that in this stadium, you can't play the ball backwards when you have the chance to play it forwards.
"The first time you do that, you hear the groans and I can understand why.
"We have to be progressive with our passing and play forwards, and that was the first thing I told them.
"Don't resort to coming back, we don't want to be a side that plays 100 passes in our own half and gets nowhere.
"I thought we got the balance on that a lot better in the second half and we had more final third entries.
"The players at the moment are still just finding out about what I want, and in large parts they did it well today - apart, obviously, from the errors we made."
Mo Eisa put MK Dons in front just after half-time and, although Ross Stewart levelled on the hour, former Sunderland striker Conor Wickham came off the bench to score the winner 15 minutes from the end.
Of the type of goals Sunderland conceded, Neil said: "If it's really good play from them, you have to take your hat off to a certain extent - but it wasn't.
"We have the ball away cheaply in the middle of the pitch, playing in areas we shouldn't, and we had spoken in the week about not risking the ball in central areas.
"We wanted to work the ball from side to side and double up on them, and when we did that we looked a good team.
"When you start making rash decisions, poor decisions, it comes back to haunt you and that's exactly what happened.
"I'm still finding out about the team and the group.
"They can take information on board and carry it out, but it is just individual decision-making when we are in possession of the ball.
"We don't want to be too dictatorial on that because we want to leave some freedom for your creative and your flair players, but unfortunately today we got some of those decisions wrong."
Sunderland slid down the table from fourth to seventh, and they are now outside the play-off places on goal difference.
Neil said: "I haven't looked at the league table yet.
"I'm focusing on winning the next game against Burton on Tuesday night, and the league table will take care of itself.
"I'm not at the stage where I'm starting to fret about league tables."
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