Ospreys needed an 80th minute-penalty to claim a 26-26 draw against a spirited Treviso side in an enthralling encounter at Stadio Comunale di Monigo on Saturday.
Replacement fly-half Matthew Morgan split the uprights from long range to deny Treviso an historic Heineken Cup victory in the last minute.
Off the base of a massive effort from their impressive forward pack, Treviso outscored the Welsh side three tries to two.
Ospreys led 10-9 at half time as the Italian club went toe-to-toe with their more fancied visitors. But second-half tries from Michele Rizzo, Benjamin de Jager and Tobias Botes saw Treviso move ahead.
Ospreys have not lost to an Italian side in twelve games in European rugby and tries from Tommy Bowe and Ryan Jones helped them retain that record while Dan Biggar added 13 points with the boot.
Treviso came out of the blocks at a furious pace and took the early lead thanks to penalty from fly-half Kristopher Burton after an extended period of pressure.
Ospreys could have struck back soon afterwards but skipper Justin Tipuric spilled a pass with the tryline begging after Tommy Bowe had sliced through the home defence.
Bowe did however open the visitors' account at the end of the first quarter with a fantastic effort, breaking the line, muscling his way past a handful of defenders before stretching out an arm to score.
Biggar added the extras (after missing two penalties attempts) before trading place-kicks with his opposite number to leave Ospreys 10-6 up on the half-hour mark.
Burton made it three-from-three to close the gap to a single point with half time approaching when his kick bounced over off the upright.
Biggar sent a relatively easy drop goal attempt wide meaning the sides would head for the changing rooms at 10-9 to the Welsh side.
Ospreys were dealt yet another injury blow (Adam Jones pulled out earlier in the day) when scrum-half Kahn Fotualii hobbled off just before the break.
Treviso put their noses back in front soon after the restart however when a powerful rolling maul rumbled forward before prop Michele Rizzo crashed through the crowd to score.
Ospreys replied almost immediately when Biggar landed another three points to capitalise on an attack started by Shane Williams.
But Treviso were able to move further ahead when South African wing Benjamin de Jager beat Williams into the corner to give the hosts a a 21-13 lead.
However a line-out error gave Ospreys the chance to claw their way back into the game as Ryan Jones collected Enrico Ceccato's wayward throw and found his way through the traffic and over the whitewash.
Biggar's conversion meant that it was once again a one-point game, but to Treviso's advantage this time at 21-20.
That gap grew to six points though on the hour mark as Treviso scrum-half Tobias Botes finished off a wonderful move with a sprint down the touchline to score his side's third try.
The situation was almost literally turned on its head when Treviso centre Tommaso Benvenuti was sent to the sin bin for a tip tackle on Williams. Biggar found the target to cut Treviso's lead to just three points with fifteen minutes to play.
Treviso looked to have the game secured but Morgan landed a penalty from 51 metres out to save two points for Ospreys.
Tries: Rizzo, De Jager, Botes
Pens: Burton 3
Tries: Bowe, R. Jones
Cons: Biggar 2
Pens: Biggar 3, Morgan
Yellow card: Benvenuti (Treviso - 62nd min -tip tackle)
Treviso: 15 Ludovico Nitoglia, 14 Benjamin de Jager, 13 Tommaso Benvenuti, 12 Alberto Sgarbi, 11 Brendan Williams, 10 Kristopher Burton, 9 Tobias Botes, 8 Robert Barbieri, 7 Alessandro Zanni, 6 Benjamin Vermaak, 5 Cornelius van Zyl, 4 Antonio Pavanello, 3 Lorenzo Cittadini, 2 Enrico Ceccato, 1 Michele Rizzo.
Replacements: 16 Franco Sbaraglini, 17 Ignacio Fernandez Rouyet, 18 Pedro di Santo, 19 Valerio Bernabo, 20 Gonzalo PadrÃ², 21 Manoa Vosawai, 22 Willem de Waal, 23 Fabio Semenzato.
Ospreys: 15 Richard Fussell, 14 Tommy Bowe, 13 Andrew Bishop, 12 Ashley Beck, 11 Shane Williams, 10 Dan Biggar, 9 Kahn Fotualii, 8 Jonathan Thomas, 7 Justin Tipuric (c), 6 George Stowers, 5 Ian Evans, 4 Ryan Jones, 3 Aaron Jarvis, 2 Richard Hibbard, 1 Duncan Jones.
Replacements: 16 Mefin Davies, 17 Ryan Bevington, 18 Cai Griffiths, 19 Ian Gough, 20 Joe Bearman, 21 Rhys Webb, 22 Matthew Morgan , 23 Tom Isaacs.
Venue: Stadio Comunale di Monigo
Referee: Pascal Gauzere (France)