Amorim takes charge for the first time today at Ipswich.
Keane said: "You're always hopeful when a manager comes into United he can come in and get United back up competing at the top. It's not quite happened the last few years. I think the PR over the first week from the new manager has been good, he’s spoke well, been very positive, a lot of talk about changing systems.
"He’s a young manager, very hungry, looks like he can hopefully deal with the pressure. But being honest, nobody knows until he gets into the job properly and that’s getting games under his belt. You hope today they can come and beat Ipswich, put a marker down, get the team competing.
"It’s probably just more hope than anything else until he gets into the job and he sees what the real problems are.
"No matter what position United are in you’d like to think they can come to Ipswich and get a result. I think for all United’s problems it is the lack of goals. We talk about United having a lot of good, talented players but we don’t see it in terms of the goals. The goals ratio is really poor. That’s certainly an area he needs to improve, on top of all the other ones he’s got."
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