MILLWALL boss Neil Harris couldn't hide his displeasure at his side's defending in the 3-2 defeat to Barnsley on Tuesday night.
The Lions lost their second home game in four days courtesy of Lewin Nyatanga's stoppage-time winner on a brisk autumnal evening in south London.
And Harris said he has questioned the players' characters after a third consecutive defeat in all competitions at The Den.
"I can't repeat what I said to the players afterwards," Harris said. "They know in no uncertain terms of my dismay at the defending.
"I said to the players, 'who's taking responsibility on set-plays, who's reminding the players to keep the ball out of the net?'
"That's a big thing for me, the leadership in defending. I'm disappointed at the three set-plays we conceded.
"Two of them were second-phase balls and one went straight into the goal. Conceding from set-plays hasn't been a common theme under my stewardship."
Harris added: "What has been common, though, is that we've conceded goals this season and that's the headache for me, that's what I have to put right and for that I question the character of the players, that's for sure.
"I don't think we got a foothold in the game after half-time, I think we can have a pattern to our play and a game plan but I'm not putting out a team of robots.
"They have to make decisions and think for themselves. I give them that responsibility to be able to do that. I didn't feel like we controlled the game at all at the start of the second half.
"The biggest thing is we had spells on top and when you score when you're having good spells, it's great, but when you're under the cosh a little bit you have to defend.
"I spoke to the players before the game and said if we have a five-minute spell where we aren't in control of the football match, under no circumstances does that ball end up in our goal.
"It happened twice – once in the first and once in the second half. What topped it off was the goal in injury-time. It's criminal for a home team to defend like that from a set-play in injury-time."
Fred Onyedinma had given Millwall a 27th-minute lead with his first goal for the club, and the 18-year-old attacker then equalised when he headed in Shane Ferguson's corner eight minutes from time.
And Harris said that while it was hard to think positively after the defeat, Onyedinma's performance and goals were the main highlights.
"I'm delighted for Fred. We all know what a talent he is and what we think he will turn into.
"He deserves his goals not just for the way he plays but also his attitude for the game.
"The performance was better than Saturday but Barnsley are a passing team so they're going to have more possession, the stats will probably show that."
"Again, we've had chances and there were some good passages of play in both halves.
"We worked the ball into wide areas and put dangerous balls in the box, scored two very good goals and could have had a few more.
"The positives are there definitely but, other than young Fred, it's difficult while it's raw in my mind to be positive after the game when we've lost another one at home."