The 19-year-old delivered superb performances on consecutive nights to lift both the junior singlehand and the men's singlehand championships.
The junior final against Lyle Hunter was expected to be a tough encounter but Duncan dominated play from the start, and turned out a comfortable winner.
The men's final saw him up against an in-form Ian Humble who was making his third consecutive appearance in the final.
Once again however, Duncan was in tremendous form and dominated the match.
While Humble played some great saving bowls, the constant pressure made it difficult to pick up shots and find a way back into the match.
A very impressive run of 2s and 3s saw the teenager power to the finishing line and complete the double by a margin of 21 shots to 8.
The ladies' singlehand final also turned out to be a one-sided affair with Sarah Ewing dominating from start to finish in defeating Kate Cullinan.
In a closely-contested senior men's final, Robert Toshack came out on top by 21-18 over David Goodwin while the winners of the senior pairs were Ricky Borthwick and Donald Waite, who triumphed by 7 shots over Graham Bratcher and Eddie Cathcart.
Both the men's 2-bowl pairs, and the men's pairs finals were won convincingly by J J Watson and Jim Roxburgh who were always well in control of the matches against Graham Martin and Ross Kinnell, and then Colin Martin and Donald Waite.
The outdoor season began on Friday 12th April with the green being officially opened by Lena Cook.
This was followed by the opening friendly against Dunfermline Bowling Club for the Andrew E Wilton Trophy which resulted in victory for Headwell by 70 shots to 50.
In the first away friendly, Headwell visited Edinburgh's Summerside Bowling Club in the annual contest for the Forth Trophy and in a very close match came out on top by 103 shots to 97.
This week sees another away fixture with four rinks travelling to take on Methilhill BC on Saturday.