Posted 4th August 2014 at 03:26 pm
Young Scottish striker joined Blues at end of July on a three-year deal after leaving Scottish club Celtic.
Born in Dumfries, Johnstone was a product of Celtic's Academy.
The Scotland U19 international is a highly-rated prospect who attracted a host of potential suitors after turning down a fresh contract offer from the Hoops to test himself in English football.
The powerfully built front man is extremely competitive and also shows terrific movement in and around the box.