Rooney was reacting to Amorim's claim that United want to win the Premier League after being dumped out of the FA Cup at home by Fulham.
Amorim said, "The goal is to win the Premier League.
"I know we are losing games but the goal is to win the Premier League again. I don't know how long it will take. We have a goal and we continue forward no matter what."
Rooney said on Match of the Day: "I think it's a little naive to say they're looking to win the Premier League because from where they are now, they're a long way off that.
"I think he'll get time but it's not a free hit because he'll expect more from Manchester United than what we're seeing since he's been in. He says winning the Premier League, how can they compete? To get further up the table, I think that's the next step for them."