The 25-year-old has scored seven goals in seven games - form that won him December's Clydesdale Bank Player of the Month award.
"He's got such a good touch for a big fellow," the Dons boss said.
"He's great in the air and is a good finisher.
"Maybe I shouldn't be saying this until February 1 but I've got to be honest, he's a great player.
"You are always worried about (losing good players).
"You never know in this game but I would think he'll still be at Aberdeen right to the end of the season and hopefully a bit longer."