The Red Devils overturned a 12-4 halftime deficit to storm to victory, but it was the way they applied themselves to preventing the Robins from scoring which pleased the Welshman most.
“You win games on your defence and you win tight games with your defence,” Harris told his club’s official website.
“We play a lot of good teams who throw a lot at you.
“If you can defend you’ll have to score 40 points every week to win.
“We’re still long way away but we’re making good strides.”
Harris still feels that there is room for improvement, however, particularly in attack.
“Our attack is not brilliant at the moment but we’ll get there going forward,” he explained.
“I don’t thing we were white hot but because we were solid defensively we kept the scoreboard ticking over.
“That’s when you become dominant.”