A brace from Glenn Murray was enough to grab all three points, and the striker could have had more had he scored his second penalty of the match.
Fleming reserved special praise for Murray and believes that the win was a result of work being put in on the training ground.
"We are a hard-working team, we don't get too carried away. What you see is Saturday but we work at it Monday to Friday," said Fleming.
"Glenn's began fantastic this season and he works so hard for the team. Let's not think about the one he missed but the one he scored. We go forward when we can but we have a structure. You can see the energy we have.
"It's all cliches but I'm working as hard as I can whilst I'm contracted to Crystal Palace. I will work until I know any different."
The win lifts Palace up to third in the Championship table.