Sean O'Driscoll was critical of his side's ball retention after seeing Doncaster outplay Newcastle for long periods at St James' Park only to lose 2-1.
Dean Shiels put Doncaster ahead and Martin Woods missed a penalty, while Newcastle, who had Zurab Khizanishvili sent off in a frantic finish, equalised through Andy Carroll and secured the win thanks to Kevin Nolan's 92nd-minute winner.
O'Driscoll said: "I would have said the same had we won 1-0, drawn 1-1 or lost 2-1. We need to be better with the ball.
"For us that's the big aim. When you come off a game you need to learn from it and just because we've lost I can't throw my toys out of the pram and moan about things I don't think are relevant.
"We're disappointed, but if we want to turn a 2-1 defeat into a 2-1 win then we have to be better with the ball."