Benetton Treviso staged a superb comeback before holding out with only 13 men in the dying stages to secure a surprise 20-17 Pro14 win at Edinburgh.
The visitors had lost their two outings this season ahead of Friday's trip to Myreside, while Edinburgh had won both previous matches, but the tables were turned in stunning fashion.
It looked as though Edinburgh would continue its 100 per cent start as it took a 14-0 lead midway through the opening half, Chris Dean crossing the whitewash on both occasions.
But Angelo Esposito's converted score and a penalty from Ian McKinley ensured the deficit was just four at the break.
That combination of a McKinley kick and an Esposito try proved fruitful again in the second half for the visitors, who took a 20-14 lead.
Duncan Weir brought Edinburgh back to within three from the tee but, although Treviso saw Cherif Traore and Alberto De Marchi sin-binned in the final five minutes, the visitors' 13 men held on grimly for a famous win.
Elsewhere, champion Scarlets was beaten by a late show at Ulster, which scored 10 points in the final seven minutes through John Andrew's try and the boot of Christian Lealiifano to secure a 27-20 success.
The Dragons got their first win of the campaign with a 21-8 defeat of Connacht, Gavin Henson kicking 11 points after tries from Hallam Amos and Elliot Dee.