Experienced Kiwi fly-half Jimmy Gopperth kicked half of 14-man Wasps' points as they stunned holders Toulouse 30-22 in the European Champions Cup on Saturday.
Gopperth, 38, made his contribution from the boot as the English hosts played more than 45 minutes without full-back Jacob Umaga who was sent off for a dangerous tackle.
The French club, who won a record fifth continental title in May, remain in the top eight places in Pool B and in line for a spot in the last 16.
"That took a lot of effort. When you go down to 14 men, especially when it's someone in the backfield, you have to manage the game," Wasps head coach Lee Blackett told reporters.
"We started to move the ball really well and we managed to get field position with some good attacking kicks. How we managed the red card is the most pleasing thing," he added.
Toulouse were without world player of the year Antoine Dupont but the scrum-half's Test and domestic team-mate Francois Cros scored within the opening two minutes.
Despite the positive start Toulouse trailed 14-7 after half an hour as Gopperth converted tries by Biyi Alo and Brad Shields for the home side.
Umaga, the nephew of ex-New Zealand captain Tana Umaga, was sent off after 33 minutes for making contact with away scrum-half Martin Page-Relo's head in a tackle.
Thomas Ramos then added three points to make it 14-10 at break.
Gopperth kicked two penalties to increase the hosts' lead to 20-10 after an hour before France hooker Peato Mauvaka closed the gap to five points with a try from a rolling maul.
The result was sealed with 12 minutes left as flanker Alfie Barbeary crashed over from short range. Gopperth added the extras and a late penalty.
Substitute Emmanuel Meafou claimed a late consolation for the champions who welcome Cardiff to Stade Ernest-Wallon next weekend.
Later on Saturday, three-time runners-up Racing 92 head to the Ospreys and English Premiership leaders Leicester Tigers travel to Irish province Connacht in the pick of the ties.
On Sunday, the Scarlets visit Bordeaux-Begles in one re-run of the fixtures cancelled in December before Japan full-back Kotaro Matsushima starts for Clermont at home to Sale Sharks.
On Friday, England fly-half Marcus Smith inspired Premiership champions Harlequins to a 33-36 win at Cardiff.