Wasps full-back Jimmy Gopperth kicked a last-gasp conversion to rescue a draw against Toulouse.
The first half ended 6-6 courtesy of two penalties apiece but both sides showed more ambition after the break.
Census Johnston rumbled over after a Danny Cipriani kick was charged down, before Josh Bassett levelled things with a try in the left-hand corner.
A try from Gael Fickou seemed to have sealed the win but Nathan Hughes went over before Gopperth stepped up.
The draw means Toulouse have not won any of their past six games in the competition and lie third in Pool 2 behind Connacht on nine points and Wasps on seven.
The first half was a gritty affair, the visitors frustrating Toulouse with some stout defending in a hostile atmosphere at the Stade Ernest-Wallon.
Wasps fly-half Cipriani produced a try-saving tackle on the stroke of half-time and the score was 6-6 when the whistle went, courtesy of two penalties apiece from Sebastien Bezy and Gopperth.
A half-time altercation between Toulouse lock Yoann Maestri and Wasps strength and conditioning coach Dan Baugh seemed to be a spark, with the game opening up after the break.
Having held out for so long, Cipriani gifted Toulouse a try nine minutes into the second half when his ambitious kick was charged down and Johnston rumbled over.
Wasps hit back with a try from winger Bassett only for the hosts to take the lead again when replacement Semi Kunatani fed Fickou who scampered over next to the posts.
But Kyle Eastmond found space in the Toulouse defence before finding Matt Simpson, who fed Hughes for the try.
Gopperth had a lot of work to do with the conversion from out wide but drilled the ball between the posts.
Toulouse: Medard, Huget, Fickou, David, Perez, Flood, Bezy, Baille, Tolofua, Aldegheri, Maestri, J. Tekori, Cros, Dusautoir, Axtens.
Replacements: Doussain for Flood (56), Steenkamp for Baille (56), Ghiraldini for Tolofua (56), Johnston for Aldegheri (41), Lamboley for J. Tekori (60).
Not Used: T. Gray, Fritz, Kunatani.
Wasps: Gopperth, Wade, Daly, Eastmond, Bassett, Cipriani, Robson, Mullan, Taylor, Cooper-Woolley, Launchbury, Symons, Johnson, Young, Hughes.
Replacements: Leiua for Bassett (65), Bristow for Mullan (71), Moore for Cooper-Woolley (41).
Not Used: Cruse, Myall, Thompson, Simpson, Miller.
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