Josh Bassett scored a try two minutes from time as Wasps reached their first Premiership final in nine years with a thrilling victory over Leicester.
Kurtley Beale helped Wasps build a 10-point lead but Peter Betham’s try saw Tigers three points down at half-time.
Leicester led when Telusa Veainu dived over, and Freddie Burns’ kick had them four points up and defending bravely.
Thomas Young spurned a chance as Wasps pressed but Bassett scored in the corner to set up a final with Exeter.
Premiership player of the year Jimmy Gopperth, who kicked 11 points, missed the conversion but Dai Young’s side saw out the closing seconds as Leicester fell at the semi-final stage for the fourth consecutive season.
Wasps, who finished top of the regular-season table, will face Exeter – who were second – at Twickenham on Saturday, May 27 at 14:30 BST for the right to become champions.
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A close shave
Wasps have not lost a league match at the Ricoh Arena since December 2015 and were 18 points clear in the final table of their fourth-placed opponents.
However, they were moments from being stunned by Matt O’Connor and his Leicester team, with the home side’s line-out a constant area of concern.
With the match in their control, Wasps conceded two quick-fire penalties before the influential Burns, who will join Bath this summer, launched a pinpoint pass for Betham to finish and level.
An injury forced Australia superstar Beale off early in the second half which further encouraged Leicester, who isolated the largely anonymous Christian Wade to edge in front through Veainu.
The favourites looked to have missed their chance when back-rower Young misplaced a pass to the onrushing Gopperth after breaking the line, but resilience from Guy Thompson and Joe Launchbury opened things up for Bassett to score the match-winning points.
Leicester’s season of transition
At one stage it looked like being a dismal campaign for the 10-time Premiership winners, who sacked director of rugby Richard Cockerill in January after almost eight years at the helm.
There was a real possibility Leicester would miss out on the play-offs altogether for the first time in 13 seasons, but under O’Connor they put together enough wins to keep that streak intact.
Ahead of the semi-final with Wasps the players rallied around captain Tom Youngs, who led out his side just weeks after learning of his wife Tiffany’s terminal illness.
The Lions and England hooker, in his 100th start in a Tigers shirt, was part of a much-improved performance from the Tigers pack as O’Connor’s side came within two minutes of reaching the Premiership final at the end of a season of transition.
Leicester head coach Matt O’Connor told BBC Radio Leicester:
“It’s hard to describe really. We didn’t deserve to lose, I thought we did enough.
“At stages I thought we were fantastic, for the majority of the game. They just asked too many questions of us.
“This year is about perspective. You dust yourself off and make sure you’re better next year.
“I think results have shown over the past four or five weeks that there’s a lot of growth in the individuals we’ve got.”
Wasps: Beale; Wade, Daly, Gopperth, Le Roux; Cipriani, Simpson; Mullan, Johnson, Swainston; Launchbury (capt), Symons; Haskell, Young, Hughes.
Replacements: Taylor, McIntyre, Moore, Gaskell, Thompson, Robson, Leiua, Bassett.
Leicester: Veainu; Thompstone, Tait, O Williams, Betham; Burns, B Youngs; Genge, T Youngs (capt), Cole; Barrow, Kitchener; Fitzgerald, O’Connor, Hamilton.
Replacements: McGuigan, Bateman, Balmain, Slater, M Williams, Harrison, Roberts, Smith.
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