Millwall boss Neil Harris stated his displeasure at Millwall's 1-0 pre-season friendly defeat to Barnet on Saturday afternoon at The Hive.
John Akinde's 19th-minute strike settled a tepid affair on a rain-sodden pitch, with the manager claiming after the game that his side "defended like a League One team."
The Lions now have two pre-season matches remaining - at Stevenage on Tuesday night and at home to Granada Club de Futbol next Saturday afternoon - before the Sky Bet Championship campaign begins with a trip to Nottingham Forest on 4th August.
"I'm disappointed with the game," he said. "Results have no bearing on the League season, but the games are still important.
"It's a really poor goal to give away. We've defended like a League One team. I won't accept that.
"Our use of the ball was really poor, especially in the final third. I thought we looked really sloppy and laboured. I'm disappointed with the boys - I have to be honest.
"Pre-season is difficult. You work at such a high intensity for so many days, it's hard when it comes to games. The quicker we get into the League season, the better."