The New Zealand international, who was available on a free transfer, has joined Aberdeen on a two-year contract.
Brown said: “I felt we’d have a good season before we signed Rory but I am now sure of it. I’m delighted to get him as we only had three strikers at the club and no outfit can operate with that few.
“He is a good addition to the squad but I still think boys like Scott Vernon, Darren Mackie and Josh Magennis will get goals.
“What Rory does is give us options and that’s important as everyone knows we haven’t scored often enough so far this season.
“He’s not a battering ram striker. He is a big lad but he has a good touch and can link up play effectively as well.”
