Overturning a two-shot overnight deficit, the Lanarkshire man claimed his second victory in the PGA Professional Championship by finishing four shots ahead of fellow Scot Greig Hutcheon.
In closing with a 66 to finish with a 20-under-par 269 total, he also won the PGA Play-Offs being staged simultaneously at the Perthshire venue by a resounding eight shots.
O’Hara, who also triumphed at Luttrellstown Castle in Ireland in 2017, is the first player to win the PGA Professional Championship for a second time since Bob Cameron achieved the feat.
Three straight birdies to start set the tone for O’Hara in the final circuit before further gains at the ninth, 11th and 18th in a bogey-free effort helped secure the £10,000 top prize.
“I knew I had a good lead and just had to use my head - the course can beat you very easily round here,” said O’Hara.
The success followed a string of victories over the past few weeks on the Tartan Tour, including a second Northern Open victory at Portlethen.
While it wasn’t to be for Hutcheon in his bid to claim the missing link on his CV, it was also a fine week’s work from the Torphins Golf Club-attached player.
Helped by a birdie at the penultimate hole, he signed off with a 72 to pip 2016 champion Higgins (69) for second spot as they joined O’Hara in picking up the bulk of the points in the battle to make next year’s PGA Cup team.
Alastair Forsyth, the 2019 winner, secured a top-10 finish with a closing 69 that was illuminated by an eagle-3 at the 17th.
On the Challenge Tour, joint-overnight leader Ewen Ferguson had to settle for a share of second spot behind home player Santiago Tarrio in the Challenge de Espana in Cadiz.
Hopes of a Scottish success were also dashed on the PGA EuroPro Tour as Callum Fyfe, who led by two shots at the start of the day, finished fifth behind Englishman John Parry in the Cumberwell Park Championship.