Wasps fear "serious repercussions" after the controversial end to Saturday's European Champions Cup clash with Connacht.
Dai Young's side was beaten 20-18 at the Galway Sportsgrounds but the Irish province's winning try came long after the 80 minutes had elapsed.
Connacht were allowed to take a line-out by referee Mathieu Raynal, who had replaced Jerome Garces earlier in the game, despite protests from Wasps bench and Naulia Dawia went on to score a try to level the scores.
Jack Carty then made the conversion to secure victory and leave the sides tied on 13 points, the same amount as Toulouse, in Pool 2.
European Professional Club Rugby said on Sunday that the result would stand and, while Wasps have accepted that verdict, they made the disappointment known in a statement on Monday.
The statement read: "Wasps' pitchside officials immediately stressed to the fourth official that Connacht could not take the lineout, as the referee had indicated time had gone beyond 80 minutes.
"We all understand referees are only human and mistakes do occasionally happen. However, for a referee and 4th official to get the laws of the game wrong at a crucial stage of a big match is hugely disappointing. The error made could have serious repercussions in terms of Wasps' qualification hopes or the prospect of securing a home quarter final.
"EPCR have stated that the result stands. We congratulate Connacht after a hard fought contest and we will now move on to the final rounds, after tough Premiership games against Bath, Newcastle and Leicester Tigers."
Click on the attached video to hear Will Greenwood's thoughts on the controversy in Galway on Saturday.