Gary Rowett acknowledges that whilst Millwall's second-half performance at the Madejski Stadium against Reading showed a lot of character, The Lions' first-half display cost the team a result in Saturday's Sky Bet Championship meeting.
The manager has given an assessment of a game which his side trailed 2-0 at the break through Jordan Obita and Sam Baldock's strikes.
An excellent solo goal from Jed Wallace halved the deficit shortly after the hour mark, but The Lions leave Berkshire without a share of the points.
"We left ourselves with a mountain to climb after the first half, which I was disappointed with due to our quality on the ball at times, not putting enough balls into the area, and playing safe and secure which didn't help us," Rowett says.
"The goals were poor to concede. The first goal - it looked like a foul on Willo in the process, however it's a good finish from their player. We did need to get out towards them quicker. The second goal, we don't cover quickly enough and, again, it's a wonderful finish.
"I just felt we were too passive first half. If you look at Saturday's performance, we were snapping away and we played very aggressively. Here, we were very passive and then our goal changed everything. Our mentality was much better, we changed formation just to try and get out quicker in midfield, and as soon as the goal goes in, we start winning tackles, getting on the front foot, and attacking quickly."
The boss says the gap between the tenacity shown at The Den and on the road must be bridged quickly in order for The Lions to properly pick up momentum.
"If the game was another five minutes longer, I'm sure we would have got a equaliser. The disappointing factor was that it took a goal to change our mentality for the better. I'm fairly pleased with the second half, which we will look to build on.
"I said to the players that it's only our second game, and I don't expect them yet to get every tactical aspect we're after, or to play every game with great quality, but what we do expect is that aggression. To play so well that way at home and be so close to deny space to the opposition, but then to be slow with that on the road against the very good players Reading have, was frustrating.
"Regarding the goal, it was a fantastic piece of individual play from Jed. We've spoken before about that unpredictability he has, and that spark that you need in games. We didn't have that from the team in the first half - we were a little reluctant to put the ball in the box - but certainly, Jed's goal was excellent. We created more towards the end, a great chance we had for Jon Dadi as well, and I couldn't ask for an awful lot more from the players in the second half."
Rowett claims it is imperative the positives are built on, with another full week of training now about to get underway before next weekend's South East London derby against Charlton Athletic, back on home turf.
"We just have to pick at every performance. We're all of course disappointed and want to win every game, and we want to come here with a mentality that we can get on the front foot and play like we do at home, but we just pick the bones out of it.
"We have to improve and try to learn from those improvements - we're learning more all the time. I was very tempted to do something slightly different away from home, but I just felt the display last week was so good that we wanted to see if they could build on it. So, from my perspective, I've learnt an awful lot in my first away game - that the character of the team's good - but we need to start with that character.
"I thought the fans stayed behind us as well in the second half, really helped the team massively, and we'll stay calm two games in, we've won one and lost one. We're a bit disappointed, but at least we've got some positives moving forward."