Four shots clear of playing partner, Catherine Panton-Lewis (pictured), in the Glenmuir Women's Club Professional Championship, Tracy ran up a calamitous seven, and, as if to deepen the wound, Cathy holed for a birdie two.
The Scot, daughter of golfing legend, John Panton, then took a vice-like grip of the championship by adding three successive birdies from the 16th, her piece de resistance delivered at the last with an unerring 20-footer.
As Tracy signed for a disappointing 78 for 150, Cathy won the title by three shots with a best-of-the-championship 71. Lysa Jones and the holder, Mette Hageman, tied third on 151.
Said Catherine, whose birthday was yesterday: "My dad will be thrilled. He's in his 91st year and lives above my husband Phil (who caddied for Cathy) and myself in Berkshire. We still play nine holes together - it's great having your coach living upstairs!"
A deep-faced pot bunker was the cause of Tracy's troubles. She took three to extricate herself, the third attempt flying over the green. A chip and two putts later meant she was irretrievably on the back foot.
But the Scot's brilliant finish meant a well merited victory, worth £1,000