The Liverpool-born striker cannot wait to be reunited with Mexican front-man, Javier Hernandez, who with Rooney, combined to score 24 goals last season.
Chicharito, as he is known affectionately by fans, missed United’s opening EPL fixture after being out with concussion, after being struck on the head by a ball during a training session in United’s pre-season tour of the USA.
Danny Wellbeck has since been selected ahead of the diminutive forward, but suffered a hamstring injury in the champion’s last match against Arsenal, thus paving the way for him to be reunited with Roo.
"I'm looking forward to him doing the same, if not scoring more goals for us, this season," Rooney told MUTV.
"Of course people know about him now but, if you look at all the top players around the world, people know how they play and it's still difficult to stop them."
However, Rooney explains why his strike partner will remain a menace to defenders across the league and not succumb to the phenomenon of ‘second-season-syndrome’.
“His movement is so good it's difficult to defend against. It won't be easy for players to defend against him whether they know about him or not.
“It's great to have a lad who has just come into the team, who speaks good English and is always smiling,” added Rooney.
United will be hoping to stay atop the EPL when they travel to Bolton on Saturday evening.