Dai Young declared Wasps had emerged from the "dark days" after staging their Aviva Premiership clash with Gloucester at Twickenham.
A crowd of 38,296 watched James Haskell run in two tries and Tom Varndell, Elliot Daly and Ashley Johnson also cross in a 38-30 victory that failed to reflect the London club's dominance.
The win, combined with Exeter's 55-12 rout by Sale, means Wasps replace the Chiefs in seventh place to improve their chances of securing the play-off route into next season's European Champions Cup.
Two seasons ago the four-times Premiership champions almost entered administration, but Young hailed their return to Twickenham as a defining moment that marks the conclusion of a trouble period in their history.
"I said to the players that this was a celebration for us coming out of the dark days, not totally on the pitch but certainly off the pitch," the director of rugby said.
"We couldn't have dreamt of staging a day like this over the last two seasons.
"We're back staging big games and big events, showing how far we've come off the field over the last 10 months.
"I was pleased with the crowd, which is a massive achievement for a first up.
"It sends a message that we're out of the dark days and can plan things now.
"We're in a much better position as a club and the future is exciting."
Wasps' back row of Haskell, Johnson and man of the match Nathan Hughes were superb throughout, but Young was disappointed that Gloucester were not dispatched more convincingly.
"We scored five tries and gave them two. We were very good in patches but very loose in patches as well," he said.
"We probably won that game four times over and the score flattered them. We made harder work of it than we needed to.
"At critical moments of that game, our pack really stood up.
"Nathan Hughes was outstanding, Ashley doesn't know how to play poorly and was a bundle of energy. James Haskell was very good, but I'm sure he'll tell you that himself.
"There were two England squad players in Gloucester's back row, but our back row totally outplayed them
"I said to the players this is not an exhibition game because we were certainly buying into the party.
"We were trying things that weren't on and created our own downfall."
Gloucester's challenge for the European play-off is all but over with a seven-point gap having opened up on Wasps. Director of rugby Nigel Davies remained upbeat despite the result.
"Our first up tackles and the line-out cost us the game. We gave away a very soft try before half-time. We didn't take our opportunities," Davies said.
"We played with good intent and it's frustrating that first up tackles weren't made, but Wasps have some big ball carriers.
"If we hadn't given two very sloppy tries away, things would have been decent. I'm disappointed, but we played some good rugby at times."