Christian Wade looked to have won a footrace to score in the dying minutes but the whistle went the home team’s way and the last minute chance was gone.
In truth it would have been harsh had Wasps stolen the victory right at the end, as a fired up home side fought valiantly for a much needed win having lost six in a row.
Wasps got off to a bright start with an early dart from Elliot Daly, playing in the unfamiliar number 15 shirt.
A charge-down on Gareth Davies from Tinus Du Plessis led to a decent passage of play for the visitors which ended with a first shot at goal for youngster Tommy Bell playing at fly-half. Bell’s kick, in the rain, was pushed just wide.
But Wasps continued to press, and got within a whisker of scoring a try just minutes later.
A fine take from Jonah Holmes saw Cardiff penalised as they chased the kick in an offside position, and Wasps were into the Cardiff 22. Wentzel caught the lineout well and Wasps drove forward but were frustratingly penalised on the floor as they repeatedly drove for the line.
A period of kicking followed and came to an end when Wasps were penalised for a forward pass on the halfway line.
That mistake proved to be extremely costly as it directly led to the first score of the night for Cardiff.
The ball was moved quickly from the scrum and with Lee Thomas slipping as Cardiff moved wide quickly, fullback Dan Fish sprinted through the outside cover to score. The conversion from Gareth Davies made it 7-0 after 15 minutes.
Wasps had a chance to hit back immediately when Tommy Bell was handed a second shot at goal and this time he didn’t miss making it 7-3.
Wasps though couldn’t clear their lines from the restart and a poor clearance kick gave Cardiff a lineout just metres out. The home side though couldn’t take advantage of the excellent field position and solid Wasps defence pushed them back up the park.
Wasps then enjoyed a fine period of possession as Sam Jones, James Cannon, Phil Swainston and Billy Vunipola were all prominently involved in some fine carries over a ten minute period, and Bell made it 7-6 after the home side were penalised for pushing offside in the middle.
But Wasps were guilty again of fluffing the restart with Wentzel knocking on as he moved forward and Cardiff were suddenly in a great position despite a thumping tackle from Chris Bell in midfield.
Davies was handed another shot at goal after a half charge down on Holmes led to a penalty but the home side’s kicker missed and pushed it wide.
Wasps then had to survive an excellent attack by Cardiff as Davies and Tom James broke away down the right. A scramble defence managed to get back and defend well with Jack Wallace and Christian Wade doing just enough, and Cardiff were pinged at the breakdown.
Wasps then raced through for their first try.
A shove at a Cardiff scrum gave Wasps a free-kick and Vunipola tapped fast and then spun a pass out to Elliot Daly who raced through a gap and finished brilliantly in the left corner under serious pressure from the Cardiff defence. Wasps took a 7-11 lead as Bell’s kick went wide.
Wasps did deal with this kick off better, winning the ball and then setting up an excellent driving maul which made about 30 metres. There were rewarded for that fine effort with a penaltuy which Bell knocked over for a 7-14 halftime lead.
Wasps pressured Cardiff at a couple of early scrums in the second half but were caught offside when pushing up in defence and Davies made it 10-14 just three minutes in.
A period of scrappy play followed, with Cardiff just shading the forward exchanges but both sides were guilty of loose errors on the floor.
The ball continued to exchange hands but Cardiff got their tails up with a well organised mail which brought them from the halfway line into the Wasps 22. As the ball moved wide, Chris Bell pushed up too soon in the middle and despite his excellent tackle, was penalised but Davies couldn’t take advantage of the penalty offer as he pushed it wide again.
Wasps then had a shot just minutes later when a penalty from another excellent scrum handed Bell the ball on the tee just 30 metres out. He made no mistake despite being heckled as he made his run up to restore a 7-point lead for Wasps.
Charlie Davies then came on for Jonah Holmes in the first sub of the night.
Tom James then grabbed Cardiff’s second try of the night when Ceri Sweeney, on for Davies, made an immediate impact with a fine wide pass and James slid in to score in the corner. Sweeney couldn’t add the kick and Wasps still led – but now just by two points.
It was all Cardiff now as James came close again to scoring when a dropped pass by Wasps saw him flyhack through but Wallace just made it back in time to slide and recover.
Wasps brought on Matt Everard for Du Plessis.
Immediately Everard was through a huge gap after latching onto the end of a pass from TR Thomas and making 20 metres before being hauled down. Wasps pressed and pressed and were close to going over the line, but the ball was agonisingly turned over and again it was hacked downfield and this time needed Daly to race back and put it out on the 22 to prevent what looked a certain score as Cardiff sent two men racing after it
Hugo Southwell then came on for Lee Thomas as Daly moved into the centre.
Sweeney’s impact continued positively and he then grabbed a third try after darting far too easily through a number of Wasps defenders and gave his side an easy 7 points and a 22-17 lead.
Will Taylor and Dave Hughes came on for their first Wasps appearances for Swainston and Wentzel.
Wasps efforts in the final few minutes came so close to grabbing a try when Wade hacked through and looked like winning the race to score. He was pushed by Sweeney but the referee gave a knock on and the last ditch chance was missed.
The home side wound the clock down to take a 22-17 win.
15. Elliot Daly , 14. Christian Wade , 13. Chris Bell , 12. Lee Thomas , 11. Jack Wallace
10. Tommy Bell , 9. Jonah Holmes , 1. Simon McIntyre , 2. T Rhys Thomas, 3. Phil Swainston, 4. James Cannon , 5. Marco Wentzel (C) , 6. Tinus Du Plessis . 7. Sam Jones
8. Billy Vunipola
Replacements 16. Nathan Morris , 17. Tim Payne , 18. Will Taylor , 19. Dave Hughes , 20. Matt Everard , 21. Charlie Davies , 22. Tom Varndell , 23. Hugo Southwell