Oran Kearney questioned St Mirren's "bottle" after a woeful collapse against Livingston.
The fuming Buddies boss insists he was "embarrassed" after watching his players ship second-half strikes to Scott Pittman, Ryan Hardie and Craig Sibbald, cancelling out Alfie Jones' maiden goal for the Paisley outfit.
St Mirren are now just a point above rock-bottom Dundee, with Jim McIntyre's charges boasting two games in hand.
Kearney fumed: "I'm embarrassed and that is me putting it mildly. The hardest thing in this league is to get yourself in front and we managed to do that – then we show an inability to cope.
"People talk about a fear of failure, but it's a fear to win that strikes me about how we went into our shells in the second half.
"I think we lost our bottle, simple as that.
"People talk about bravery in the sense of 50/50 challenges and putting your body on the line but there is also the bravery required to go and make a pass, get your foot on the ball. It's a mindset and I think it's the mentality that was severely lacking."
Livingston manager Gary Holt, who saw his side reclaim their place in the top six of the Ladbrokes Premiership, hailed returning striker Hardie.
The on-loan Rangers marksman was making his first start in eight months following a battle with a persistent ankle complaint and marked it with the crucial goal to give Livi a 2-1 lead before Sibbald added late gloss to the scoreline.
Holt revealed he almost robbed the 21-year old of his big moment.
He said: "Ryan was actually right on the cusp of coming off. We were thinking: 'Sixty minutes, is it time to take him off?' We have a lot of games coming up and we need to look ahead.
"But me and Davie [Martindale, Livingston assistant] are sitting there saying: 'He'll get one chance – it's what he does'.
"The ball falls to him in the box and nine times out of 10 someone would hit that first time, but he has the composure to drag it onto his right foot and it's a great finish.
"That's what he is about. I'm delighted for him after so long out."
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