The Leafs are closely watching big Joe Colborne to see if he’s anywhere close to being able to make the jump to the NHL. Colborne clearly fits the bill of a physical presence down the middle much better than Turris but he might need another full season in the AHL.Colborne likely starts the season in the AHL but could replace Matthew Lombardi, Tyler Bozak or Nazem Kadri down the middle before the end of the year. Between the Providence Bruins and Toronto Marlies, Colborne scored 20 goals and 42 points.