Law hates comparisons but admits that there is a link between him and United's current superstar.
"I like Rooney," Law told the Mirror. "He's a bit of a grafter as well. He'll get stuck in. Greaves was different. He was a poacher.
"When Greaves got in or near the box, you just thought 'oh s***, no, not him' because invariably he would score.
"But Greaves never got involved in the violence. Rooney and I share an attitude that if you want to be a goalscorer, you have got to get in there and mix it.
"Defenders don't like people getting stuck in. If somebody kicks you, you've got to kick them back. Because if you don't, they will kick you again and again and again.
"Bill Shankly instilled that in me when I played for him at Huddersfield. I got into trouble a lot with referees but if somebody kicked me I wasn't going to let them get away with it.
"I was going to kick them back. They didn't like it and when they didn't like it, they didn't kick you again so that was my protection really."