"I think this season, Chelsea have a lot more pace about them," said Rooney. "They have brought in a lot of new players and really added some speed to the team. So the most important thing when we go to Stamford Bridge is to make sure that we defend well.
"If we do that then we can think about scoring some goals.
"It's been a great start to the season for them and it's clear that winning the Champions League has given them a lot more confidence.
"Mata is a great player and Hazard has settled in really well in his first season.
"I think those two - along with Torres - are the three biggest threats to us.
"Torres is still a big threat. I don't think he gets the credit he deserves because he works hard for the team and puts a real shift in.
"Sometimes the goals go in for him and sometimes they don't - but he is always trying."