"We lacked energy and we lacked legs," says the manager
Neil Harris branded Millwall's 1-0 Sky Bet League One defeat at Swindon Town on Saturday afternoon as "not acceptable."
Conor Thomas - a late inclusion to the Robins line-up - struck deep into stoppage-time to hand The Lions their first League defeat in 17 games.
The manager stated after the game that the manner of the defeat was "disappointing."
"Our quality on the ball was awful. We lacked energy and we lacked legs," he said.
"A Millwall team should be coming here today and imposing themselves on the game. We had moments of that and got into good positions with the ball, but we didn't use it wisely - that's certainly a frustration.
"The facts are one defeat in 17, but today is not acceptable. If we're to push ourselves back into the Play-Offs, then we need to perform better than that on Tuesday evening.
"The disappointment for me is the manner of the defeat. We didn't create enough chances and the players didn't show enough bravery on the ball. We looked weak mentally and physically."
With the games coming thick and fast for Millwall and with a trip to League leaders Sheffield United next up on Tuesday night, boss Harris hinted that changes may have to be made.
"If I feel some of my players have played too much football, then I'll speak to my staff and we'll make changes. You want to reward people for playing consistently well - that's been fruitful for us over the last couple of months.
"These boys have been great for me. We've got a real good group. I've been loyal to them. But it now becomes about picking the right team to win the game."
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