It was Rooney's 10th goal in as many games and the England striker knew patience would be important against the Whites.
"We knew it was going always going to be difficult coming here and they made it difficult for us," he told ESPN. "We hit the post and crossbar three times.
"We had to keep going and believe we could get the goal, and thankfully we did.
"We know we can create chances and we can take them."
"We are in a great position but we are not going to get carried away," Rooney added.