James Hanson's winner shortly before half-time means the final automatic promotion place will be contested between Rotherham and Cheltenham - barring a freak goal-difference swing - on the final day of the season, leaving Rowett to focus on the forthcoming play-off campaign.
"Automatic promotion is out of our hands - we will just focus on the player-offs. Reaching the play-offs is a great achievement.
"Gillingham come to us in the last match as champions and hopefully we can celebrate the fact we are in the play-offs. We will be as highly motivated as we always are
"All credit to Rotherham, they beat Bradford on Tuesday and have won at Plymouth today and if they win their last game that will be a great achievement.
"Losing was disappointing, but I would rather focus on the positives. I thought we were fantastic. It was as good an away performance as we have had. It was another good defensive performance and our back four were terrific.
"When you go a goal down and then a man down it is very hard work. We have given them a goal and an extra man. It is suicide - we have beaten ourselves today. At 1-0 anything can happen, but unfortunately it didn't."