Boss Dean Richards believes questionable refereeing decisions cost his side after watching NEC Harlequins let slip a 13-point advantage against Wasps on Saturday.

Centre Stuart Abbott was mistakenly sin-binned after Tani Fuga put Wasps number nine Mark McMilllan out of the game as James Haskell's try put his side 16-13 ahead midway through the second half.

Wasps counterpart Ayoola Erinle had received the same punishment three minutes earlier for flooring Paul Volley after Quins led 13-3 at the break.

And the visitors took full advantage ten minutes later with 20-year-old debutant Chris Bishay claiming the decisive score.

But Richards pointed to three earlier decisions as the turning point in a classic Jekyll and Hyde performance.

"I'm bitterly disappointed with the performance. We came out in the second half and our tactical nouse was virtually zero. We didn't play in the right areas of the field," he said.

"Stuart was totally bemused. I don't know what the touch judge was looking at, but the guy who did actually put the late tackle in, didn't have blonde hair.

"There could have been three sin-binnings in one incident soon after half-time and that was the turning point. They changed the way the game was played.

"When you're 13-6 up and going for the line and then you find yourself back in your own 22 with a penalty against you it does shake you. Very few sides come back from that."

Wasps director of rugby Ian McGeechan described his side's first away win of the season as the best in a long time after Quins dominated the opening period to go in 13-3 ahead at the break.

Fly-half Adrian Jarvis got the scoreboard ticking early on before Simon Keogh raced through untouched for a converted try straight from the training ground 13 minutes before half-time And Jarvis was on target again ten minutes later after Andy Gomarsall's break forced a penalty in front of the posts.

Van Gisbergen potted three points at the midway point and the lead was further slashed within minutes of the restart.

Wasps notched 20 unanswered points through van Gisbergen's boot and tries from number eight Haskell and Bishay, before Jarvis' penalty secured a losing bonus point for the second week running.

And a disappointed Richards, whose side are hunting a Heineken Cup spot, has hinted he could wield the axe ahead of next week's clash at Gloucester.

"I haven't really considered the play-offs, I'm just concerned with how we perform and the most disappointing thing was we just didn't perform today." he added "There will be a lot of people looking at themselves after that game and thinking I'm lucky to be in this side."