Millwall manager Ian Holloway has admitted that he was "annoyed" to see his side concede a goal so soon after taking the lead against Burnley.
The Lions went ahead courtesy of Martyn Woolford's first-half goal, although just two minutes later Sean Dyche's side were level.
Despite missing a penalty, the high-flying Clarets soon went ahead, leaving Millwall just two points above the relegation zone.
"We got a goal and I'm annoyed at the one they got back," Holloway told reporters after the game. "It was too easy. We did well up to that point. It was an uphill battle after their second goal.
"I was happy with some bits, and unhappy with some bits. In the end they beat us fair and square."
Millwall return to league action on Tuesday night when they face fellow relegation-threatened side Yeovil Town.