Jared Rosser scored a first-half hat-trick but still ended up on the losing side as the Dragons surrendered a 16-point interval lead to crash to a 34-32 Guinness PRO14 defeat at the hands of Zebre.
Italy fly-half Carlo Canna converted his own try with nine minutes remaining to complete Zebre's fightback and earn the hosts victory in a match played at the Stadio Fattori in L'Aquila, rather than at the Italian side's usual home in Parma.
The Dragons still had chances after Canna's score to snatch a dramatic win for themselves but, after having a late try ruled out by the TMO, they saw Arwel Robson's last-gasp penalty fall short.
That came at the end of an eventful encounter which saw the Dragons, seeking their first win in the competition since September, recover from 7-0 down to establish a 26-10 lead at the break on the back of Rosser's try treble and a Charlie Davies score.
Zebre rallied though, with Tommaso Castello, Tommaso D'Apice and Johan Meyer crossing in the second half to help trim the Dragons' advantage to 32-27, before Canna's decisive score settled the encounter.