Bundee Aki, left out of the Irish squad for Rome, turned from villain to hero in Treviso as he got over for a winning try in the final play at Stadio Monigo.
He had just given away a penalty in front of his posts which seemed set to give Benetton their first win of the season but Aki made immediate amends, winning the first of two penalties which saw them go to the right corner before he drove over to break Benetton’s hearts.
Connacht, with Andy Friend monitoring matters back home in Galway after being unable to travel to Italy after picking up a knee injury at the Sportsground, struggled to impose themselves after failing to build on a promising start.
Connacht dominated the opening quarter but only had a try from tighthead Finlay Bealham to show for their efforts when he squeezed over after a sustained attack on the home line after 17 minutes, with Conor Fitzgerald converting to give them a good platform.
But Benetton hit back and built the phases, with Connacht hooker Shane Delahunt binned five minutes from the break as they piled on the pressure.
And the Treviso side made them pay, with former Italian U-20 flanker Davide Ruggeri getting over beside the posts. Then a poor kick from Fitzgerald and slack defending from Peter Sullivan and Aki led to a try from distance from former Italian winger Leonardo Sarto to lead 14-7 at the interval.
Connacht upped the ante after the restart and got back on level terms inside two minutes despite being still down a man but they drove at the Benetton line and loosehead Paddy McAllister got over for his first try on his 16th appearance.
Benetton, having been pipped by Munster at the death in their last home game, enjoyed plenty of possession and looked set to finally get their first win of the season when Leonardo Padovani converted the late penalty but there was still time for Aki to rescue a fifth away win in a row for Connacht in the league.
D Ruggeri, L Sarto tries; E Padovani 2 cons, pen. F Bealham, P McAlliter, B Aki tries; C Fitzgerald 2 cons.
J Hayward; A Esposito, J Riera (R Tavuyara 70), L Morisi, L Sarto; E Padovani, D Duvenage (c); T Gallo (N Quaglio 64), C Els (T Baravalle 62), I Nemer (Z Nearchou 64); I Herbst (M Canali 62), E Snyman; D Ruggeri, M Zuliani (G Pettinelli 72), R Favretto.
T O’Halloran; P Sullivan (J Porch 59), T Daly, B Aki, A Wootton; C Fitzgerald, K Marmion (C Blade 64); P McAllister (D Buckley 20-31 HIA & 56), S Delahunt (J Murphy 66), F Bealham (D Robertson-McCoy 56); O Dowling, G Thornbury (N Murray 66); E Masterson (J Murphy 41-45) (S Masterson 68), J Butler (c), P Boyle.
M Mitrea (Italy).