Newport Gwent Dragons recovered from last week's Anglo Welsh LV Cup loss to Bath with by edging out London Wasps 29-30 at Adams Park.
A last minute penalty from Dragons fly-half Steffan Jones earned the Welsh visitors a dramatic win in High Wycombe.
Wasps outscored Dragons four-tries-to-two to earn two bonus points.
John Hart, Tom Varndell, Ross Filipo and Joe Simpson touched down for Wasps.
Phil Price and 17-year-old Hallam Amos - the youngest Welsh player to play regional rugby - went over for the visitors with Jones' boot doing the rest.
Ryan Davis kicked two conversions and Nicky Robinson added the extra points to Joe Simpson's 77th-minute try.
But home full-back Hugo Southwell was sin-binned for a late tackle on Mike Poole allowing Jones to kick the winning points.
Final Score London Wasps (17) 29 NG Dragons (21) 30
Tries: Hart, Varndell, Filipo, Simpson
Cons: Davis 2, Robinson
Tries: P Price, Amos
Con: S Jones
Pens: S Jones 4
Drop-goal: S Jones 2
Referee: Leighton Hodges (Wales)
15 Hugo Southwell , 14 Tom Varndell , 13 Elliot Daly , 12 Chris Bell , 11 Chris Mayor , 10 Ryan Davis , 9 Nic Berry , 1 Jeremy Castex , 2 Tom Lindsay , 3 Simon McIntyre , 4 Ross Filipo , 5 Marco Wentzel , 6 James Harris , 7 Matt Everard , 8 John Hart (c)
Replacements , 16 Rob Webber , 17 Zac Taulafo , 18 Ben Broster , 19 Mike Powell , 20 Joe Burton , 21 Joe Simpson , 22 Nick Robinson , 23 Dom Waldouck
Hallam Amos, Ifan Evans, Adam Hughes, Lewis Robling, Mike Poole, Steffan Jones, Wayne Evans; Phil Price, Rhys Buckley, Nathan Buck, Adam Jones, Scott Morgan, Jevon Groves, Darren Waters, Tom Brown
Replacements: Sam Parry, Hugh Gustafson, Nathan Williams, Ieuan Jones, Hugo Ellis, Joe Bedford, Jack Dixon, Matthew Jones