Captain Graeme Shinnie admits Aberdeen are “killing ourselves at the back” with a defensive fragility which needs to be fixed quickly.
The 2-0 loss to Motherwell is the 12th straight match the Dons have failed to register a clean sheet, as their winless run extended to 10 matches.
Shinnie warns the Dons cannot continue to lose “sloppy goals” as a crash in form has resulted in just three points being secured from the last possible 30.
Aberdeen’s defensive woes intensified with confirmation centre-back Gavin Molloy will be ruled out long-term by injury.
Centre-back/right-back Jack Milne is out for 12 weeks, having undergone surgery on an ankle issue.
Shinnie said: “We’ve lost two sloppy goals again – we’re killing ourselves at the back. We’re gifting teams goals and it’s putting us on the back foot every game.
“It’s not acceptable, we need to get better at it.
“In the first half before conceding the goal we were on the front foot and playing with a little more confidence.
“We had good moments in the game, but then concede that goal and it puts you on the back foot.
“The red card comes, we try to deal with it and then get into half-time and regroup.
“However, we then conceded straight from the free-kick from a straight ball and he runs in and scores – that side of it is not acceptable.”
Shinnie’s view on how to fix Dons’ defensive frailty
Aberdeen boss Jimmy Thelin is trying to bolster his defence during the January transfer window.
The Dons have made an offer to Swiss club Grasshoppers for centre-back Kristers Tobers.
Latvian international captain Tobers, 24, is out of contract at the end of the season.
The Dons’ have registered only three clean sheets in 21 Premiership games this season.
How can their defensive vulnerability be fixed?
Shinnie said: “We need to learn, because we have lost a lot of goals the same way.
“If you don’t learn from that, then it’s tough.
“Back when we lost our first game against St Mirren, we conceded a goal that day that was very similar to one against Motherwell.
“That’s something only we can change. We as a squad, with the staff, need to change it.”
Shinnie pinpoints cause of Aberdeen’s collapse
The Reds’ crash in form is in stark contrast to a 16-game unbeaten start to the season.
In early-October, Aberdeen were the only team in the top-50 European leagues ranked by governing body Uefa to have a 100% record in all competitions.
What has gone wrong during the recent slump?
“Defensively, as a team, conceding too many goals,” said Shinnie.
“If you look at the first ten game – we didn’t concede a lot. That was giving a platform to win games 1-0 or 2-1.
“We’re not doing that now.
“Against Motherwell, we looked like we were on the front foot, like the team that were dangerous and going to score.
“Then we concede and we’re 1-0 down.
“We’re not giving ourselves that defensive platform to go on and win games.
“From that side of it, it’s something that we really need to sort out.”
Can Aberdeen rediscover their form?
Aberdeen were level on points at the top of the Premiership with leaders Celtic after an 11 game unbeaten start to the league campaign.
They were also nine points ahead of Rangers.
The Dons have now dropped to fourth in the table – just four points ahead of fifth-placed Motherwell.
Do Aberdeen have the quality, and character, to rediscover their early form?
Shinnie, 33, said: “Without a doubt. The quality is in the squad – you’ve seen that in the first 10 games that we had.
“The quality is there. It’s just getting it back and that’s what we need to find.”
Dons players will back Rubezic
Aberdeen were reduced to 10 men at 1-0 down against Motherwell when Slobodan Rubezic was red-carded following an off the ball incident with Tony Watt.
Rubezic will now miss Sunday’s clash with Hearts at Pittodrie due to suspension.
Shinnie said; “He’s obviously apologetic and he knows he’s done wrong.
“But he’s one of us and we’ll look after him.
“Even down to 10 men, I thought we had control of the game.
“We just needed to get the ball in the back of the net, which we didn’t do, which was disappointing.”
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