Neil Harris says that whilst The Lions will take positives from Saturday afternoon's draw with Hull City, he has been left frustrated by the way the visitors were able to score twice without a great deal of pressure.
In a game in which Millwall spent large periods on the front foot, Hull took an early lead and later equalised after goals from Lee Gregory and Aiden O'Brien either side of half-time.
"I'm getting fed up of standing here and saying we've been frustrated, but it could turn out to be a really good point," Harris says.
"We got an excellent point last week, but we had to back it up this week with a victory. We went behind to a really poor goal where we just switched off individually.
"After that, we were excellent - we absolutely bossed the game from start to finish. We created chances, dominated possession in the first half and created a few chances - nothing majorly clear-cut but had opportunities to get into really good areas, put balls in the box and threaten."
The boss has commended his team's display in the second period, but has been left frustrated by Markus Henriksen's leveller.
"We came out in the second half and were excellent. We wanted to build on the 1-1 scoreline and the momentum was with us. We could have had three in the first two minutes of the half, but we stuck at it - Aiden scored a really good goal and I thought we were absolutely cruising.
"But then to concede a set-play goal like we did... I said to the boys that I can't remember us losing a header or competing for the second ball all game, however they've had two free headers 12 yards from our goal from a set-piece. It's not acceptable, and individually they need to do better."
Harris insists that there are plenty of good points to work with, and highlights that the back line against The Tigers were largely the same as that which kept numerous clean sheets last season.
"Of course we will take the positives out of the game. For competing like we are just shows another game where we were better than the opponent. But we haven't won the game, and you have to make sure you score on top, and don't concede when under pressure.
"They've scored two goals out of nothing, and another team hasn't cut through us. We're just conceding too many goals, and that's the defence today that kept 19 clean sheets last year. We're trying to make sure we have the confidence, belief and gameplan. However basic and direct we have to go at times, the players know their roles and responsibilities and when they deliver, it's excellent. They have to find the confidence and belief as professionals and human beings.
"What I have got is a great bunch of lads who are as honest as they come. We need some strong leadership within the changing room, and obviously it doesn't help not to have Shaun Williams. But when you go 2-1 up at The Den, you have to go on and win the game."
The afternoon did see a number of forwards return to Harris' squad - and the manager personally praised some of the top performers in his line-up.
"I thought Lee Gregory was outstanding - the best player on the pitch. Aiden grew into the game, had a great second half and scored a brilliant goal. I was able to bring Tom [Elliott] on for Steve [Morison] at the end to try and make an impact. Hutch is back to his best defensively, and Jed [Wallace] was a real threat for 90 minutes.
"But, we can go through the positives all the time, but ultimately we've only got one point when we should have had three."