The 32-year-old calls time on a career encompassing 32 caps in nine years playing for Scotland – including two World Cups and six editions of the Six Nations.
Danielli has not played international rugby since last year’s World Cup while he has only made seven appearances for Ulster in all competitions since then.
The problem hampering Danielli is a debilitating back injury and, while retirements falls on him hard, he could not think of anything else to remedy the situation.
“Having been advised that I am no longer able to achieve the level of fitness required to play professional rugby, it is with great sadness that I announce my retirement from the game,” said Danielli.
“This last year has been incredibly frustrating in that my back has not allowed me to train or play anywhere near a frequency or an intensity necessary in a professional game.
“And because of the pain, deterioration and related injuries it’s causing, I have to think about later life beyond rugby. Having said that I feel privileged to have been playing for over a decade.
“I have thoroughly enjoyed my time as a professional rugby player, particularly my last five years here at Ulster and the huge honour of representing my country.”
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