The 18-year-old pulled off a string of quality stops to deny city rivals Inverleith.
His heroics, coupled with two gifts from the visitors, almost allowed the Meggetland men to snatch a point from an entertaining Division One opener, which Inverleith won 3-2 having led 3-0.
Telford College student Hadfield, who was understudy to Johnstone last season, turned a rasping, reverse stick shot from John Harris over the bar when it looked to be heading for the top left-hand corner.
Then the 6ft 1in stopper saved a powerful drive from Adam Mackenzie and the Scotland under-21 squad member said: “I learned tons from Colin.
“It’s a big responsibility taking over from him this year, but I’m up for it.”