Ferguson, who began the week with a course-record 61 at Galgorm Castle in Northern Ireland, and was never headed, carded a closing 69 at the same venue on Sunday to finish 12-under-par, three shots clear of close friend Connor Syme and Borja Virto.
The 26-year-old, who won the Qatar Masters in March, took a three-shot lead into the final round but had company at the top of the leaderboard when England’s Richard Mansell covered his first 10 holes in five-under-par.
Ferguson responded with his third birdie of the day on the 10th and although Virto closed to within a shot thanks to five birdies in seven holes around the turn, the 31-year-old Spaniard promptly bogeyed the 14th.
With Mansell dropping shots on three of the last four holes, that gave Ferguson some welcome breathing space and playing partner Syme birdied the 15th, 16th and 18th to finish runner-up for the second week in succession.
“It feels unbelievable, just can’t believe how calm I was out there,” Ferguson told Sky Sports.
“It couldn’t have worked out any better playing with Connor.
“I played with him the first two days and he was playing so, so good and I felt he was my main rival so managing to play with him and kind of holding each other off and trying to keep up with each other was so good and I can’t believe I’m a winner again.
“My mum and dad were supposed to be here this week but the last tournament they watched didn’t go so well so I banned them because I said I needed to focus.
“My dad’s probably at the club buying the full club drinks!
“My whole family’s life revolves around me playing golf. Their happiness seems like it’s all about me and my golf.
“It’s been a good year and obviously you get times where it doesn’t go so well so I think you really need to appreciate times when you’re picking up trophies.”
Jake McLeod finished as the top Australian for the week, a final-round 69 leaving him at two-under for the tournament in joint-23rd.
His compatriot Zach Murray ended tied for 32nd after his 72 left him at one over for the week.
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