"The game went a bit dead in the second half but it's great we got the win," said Rooney. "Chelsea are a great side and you can't take anything away from them. The result could have gone either way and they played well. But, luckily for us, Edwin made three great saves."
Rooney also admitted United's pre-season trip to the Far East may have given the Reds a slight edge in a game that was played in intense heat.
"We felt okay out there. We went over to Asia and played in conditions that were quite similar. It was hot but you just have to get on with the game."