Fly-half Nick Evans converted a late penalty as Wasps kicked off their season with a 29-29 draw with Harlequins at Twickenham.
However, it was Wasps full-back Mark van Gisbergen who kept his nerve when presented with a kick to save the game four minutes from time.
Andy Powell, on his debut, and Tom Varndell had crossed for first-half tries for Wasps, while Quins' tries came through Nick Easter and Mike Brown.
Harlequins were first out of the blocks in front of a 75,000 crowd when former New Zealand fly-half Evans eluded a challenge by Simon Shaw and armed support-runner Easter for the game's opening try after only two minutes. Evans converted.
But when Van Gisbergen posted his first penalty of the afternoon, Evans replied in kind and they then engaged in a tit-for-tat kicking exhibition.
Wales back-row Powell crossed for a try of quality after 23 minutes, finishing off a move also involving Varndell and captain Tom Rees.
Van Gisbergen's conversion hauled Wasps level at 13-13, and they then stormed ahead when Riki Flutey, playing his first game back since spending a season with Brive, broke the line, took the hit while off-loading superbly for Varndell to score his 52nd Premiership try.
Another Van Gisbergen conversion edged Wasps further ahead before the accurate Evans punished a sloppy offside with a penalty.
Once again, however, the battle of the kickers continued with Van Gisbergen ending the half with a goal to reward his team's efforts.
Chris Brooker should have scored Quins' second try four minutes after the break. The hooker made a strong break, but instead of simply diving for the line he tried one step too many and ended up on his back and held up.
Quins kept battering away, and another great chance went begging when a knock-on left Easter fuming.
Wasps thought they had escaped only for Danny Care to sack Australian debutant Nic Berry at the scrum, and thisme Wasps defence led to a penalty from referee Chris White, boomed over by Evans.
Van Gisbergen's sixth successful kick edged Wasps further ahead after 51 minutes at which stage Quins lost patience with their struggling front row and rolled out the changes.
Quins launched another siege, but Wasps were content to concede a raft of penalties before referee White lost patience and handed Evans the opportunity to kick his sixth goal.
Harlequins then recaptured the lead.
As Wasps back-tracked, centres Jordan Turner-Hall and George Lowe combined just inside the Wasps 22, and the finish was delivered wide left by full-back Brown, who evaded two would-be tacklers to score behind the posts.
The conversion by Evans moved Quins into the driving-seat with 14 minutes remaining and set up a gripping last act.
Wasps won a crucial scrum just outside the Quins 22, but the expected surge did not materialise as the new-look front row held their ground and turned the ball over.
What Quins failed to do was secure the clearance and finished up fighting to keep Wasps out, a battle that ended with an offside challenge.
Van Gisbergen fired over his seventh goal of the game to haul Wasps level with four minutes to play and secure a dramatic draw.
For London Wasps:
Tries: Powell, Varndell
Cons: Van Gisbergen 2
Pens: Van Gisbergen 5
Tries: Easter, Brown
Cons: Evans 2
Pens: Evans 5
Yellow card: Worsley (London Wasps - 32 minutes)
Wasps: 15 Mark Van Gisbergen, 14 Richard Haughton, 13 Ben Jacobs, 12 Dom Waldouck, 11 Tom Varndell, 10 Riki Flutey , 9 Nic Berry, 8 Andy Powell, 7 Tom Rees (c), 6 Joe Worsley, 5 Richard Birkett, 4 Simon Shaw, 3 Phil Vickery, 2 Rob Webber, 1 Tim Payne.
Replacements: 16 Tom Lindsay, 17 Zak Taulafo , 18 Ben Broster, 19 Dan Ward-Smith, 20 Serge Betsen, 21 Charlie Davies, 22 Dave Walder, 23 Jack Wallace.
Harlequins:15 Mike Brown, 14 Tom Williams, 13 George lowe, 12 Jordan Turner-Hall, 11 Ugo Monye, 10 Nick Evans, 9 Danny Care, 8 Nick Easter, 7 Will Skinner, 6 Chris Robshaw (c), 5 Tomas Vallejos, 4 Ollie Kohn, 3 Mark Lambert, 2 Chris Brooker, 1 Ceri Jones.
Replacements: 16 Matt Cairns, 17 Joe Marler, 18 James Johnston, 19 Pete Browne, 20 Tom Guest, 21 Karl Dickson, 22 Rory Clegg, 23 Ollie Smith.
Referee: Chris White