Wasps' European hopes all but finished; Alan Gaffney's Northampton beat Clermont

James Haskell was sent off for a dangerous tackle as Wasps collapsed to a dramatic 33-28 defeat by Harlequins that all but ends their European Champions Cup quest.

Haskell flattened Jamie Roberts with a shoulder-high challenge in the 76th minute that was also late, receiving a straight red card from referee Roman Poite and ending the groggy Wales centre's afternoon.