The Ospreys suffered a chastening defeat in Scotland that hindered their chances of retaining the Welsh Shield.
Toby Booth headed to the Dam Health Stadium with a strong side - with 10 of his starting XV being Wales internationals. However, they were no match for Mike Blair's side - who marked the coach's final home match in charge in fitting fashion.
Ben Vellacott ran in the hosts' opening try before Dave Cherry added a second.
Dewi Lake replied for Ospreys but Sam Skinner, Emiliano Boffelli and Hamish Watson crossed for further Edinburgh scores before half-time.
Lake went over again, before Darcy Graham scored twice for the home side. Replacement hooker Sam Parry got another for the visitors but it was little more than a consolation.
Booth's side weren't helped by yellow cards in either half for Rhys Davies and Morgan Morris.
The defeat saw the Ospreys drop down the table Edinburgh jumped above them into 12th in the table. And now, as was expected, the Welsh Shield comes down to the clash between the Ospreys and Cardiff next week.
Toby Booth's side didn't make up any ground on Cardiff in front of them, but they didn't lose any either - with the Arms Park side falling to defeat in Galway.
Still, it leaves little room for error at Judgement Day next week if they want to overtake their Welsh rivals and retain the Welsh Shield.
Cardiff sit four points clear of the Ospreys in the race to be Wales' best and qualify for the Champions Cup, meaning Cardiff could lose and still pick up enough bonus points to stay ahead of their rivals.
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