Charlie Beech's 79th-minute try helped Wasps to a much-needed 23-17 Guinness Premiership victory over Newcastle at Kingston Park on Friday.
Touchdowns by Danny Williams and Tom May had put the Falcons into a strong position but wing Beech's late intervention handed Ian McGeechan's side the second win of their league campaign.
After just three minutes, Newcastle had taken a sensational lead following May's penalty kick to touch.
Good possession was secured at the lineout and the ball moved quickly along the line to Tane Tuipulotu for the centre to cut inside and float out a pass to winger Williams who stormed over.
Rory Clegg then made it a perfect start for the Falcons with a conversion from wide out.
Wasps got on the scoreboard after 12 minutes when Newcastle were penalised for playing the ball on the ground at a ruck and Dave Walder put over the kick, but his effort was cancelled out two minutes later by Clegg following an offside.
Walder was then on target again after 20 minutes, from a similar position to his first effort and following an identical offence.
When play swung back to the other end the Falcons worked their way into a promising position but full-back Steve Jones opted for a drop-goal attempt and was well wide of the mark.
The mistake proved costly as in Wasps' next attack, the home side were adjudged to have not released the ball in the tackle, and Walder put over his third penalty to make it 10-9 with 10 minutes of the half remaining.
Neither try-line was in danger of being crossed in the closing minutes but further indiscipline cost Newcastle dearly when they were penalised for offside after 33 minutes, and then for not releasing on moments later.
The reliable Walder slotted over both kicks to give Wasps a five-point advantage at the break.
Newcastle started the second period exactly as they had the first, scoring a fine try within three minutes of the whistle.
They had looked in trouble in their own 22 when Clegg kicked cleverly to the wing for May to take it on.
He found Jones, who cut through the Wasps defence, and although his progress was eventually halted, May was back in support to get the vital touchdown. Clegg added the conversion and the Falcons were back in front.
Wasps hit back strongly to control much of the play and could have grabbed a try when Serge Betsen chased a kick ahead only to be beaten to the touch.
Walder wasted a good drop-goal opportunity but then finally got his side back in front when Ed Williamson, the Newcastle flanker, was yellow-carded for a spear tackle, and the Wasps fly-half converted the penalty.
In a dramatic finale Newcastle pressed hard when Tim Visser was released down the left, but the Wasps defence stood firm as Williams and the Tuipulotu stretched them in their own 22.
With time running out and the game still in the balance, Wasps finally secured the winning score when they drove deep in to the home 22 and replacement prop Beech broke through a tackle to score in the corner.
Tries: Williams, May
Cons: Clegg 2
Pens: Walder 6
Newcastle Falcons: 15 Steve Jones, 14 Danny Williams, 13 Tom May, 12 Tane Tu'ipulotu, 11 John Rudd, 10 Rory Clegg, 9 James Grindal, 8 Phil Dowson (c), 7 Brent Wilson, 6 Ed Williamson, 5 Mark Sorenson, 4 Geoff Parling, 3 David Wilson, 2 Matt Thompson, 1 Jon Golding.
Replacements: 16 Andy Long, 17 Micky Ward, 18 Andy Perry, 19 Tim Swinson, 20 Tim Visser, 21 Hall Charlton, 22 Spencer Davey.
London Wasps: 15 Lachlan Mitchell, 14 Chris Bishay, 13 Josh Lewsey, 12 Mark Van Gisbergen, 11 Tom Voyce, 10 Dave Walder, 9 Eoin Reddan, 8 Joe Worsley (c), 7 Serge Betsen, 6 Dan Leo, 5 Richard Birkett, 4 George Skivington, 3 Pat Barnard, 2 Rob Webber, 1 Tom French.
Replacements: 16 Damien Varley, 17 Charlie Beech, 18 John Hart, 19 Simon Shaw, 20 Joe Simpson, 21 Hugo Ellis, 22 Jeremy Staunton.
Referee: Andrew Small
Touch judges: Don Helme, Paul Emerson
Assessor: Nigel Yates
Television match official: Trevor Parlett, David Matthews