"We'll sit down tomorrow, look at the video and look at what went wrong, and then hopefully we can rectify that on Wednesday night," Hartley said.
"We have to pick ourselves up."
"We didn't do enough in the final third, we didn't work the goalkeeper, we gave the ball away at times in certain areas of the park and we didn't really hurt United,"
"We're disappointed in terms of the manner of the goals we lost, we felt we could have avoided them.
"We got caught in the middle of the park twice and we'd spoken before the game about United pressing us. Then we got done by two set-pieces and we should have avoided that in terms of diving into challenges.
"We knew that they've got good players in the final third and we really didn't deal with it at times. We've got to give credit to United as the best team won today."