Wasps head coach Dai Young was unhappy with some of the decisions made by referee David Rose after his side lost 26-24 to Northampton at a snowy Adams Park.
Saints fly-half Stephen Myler kicked a last-gasp conversion after Christian Day had powered over to secure a victory that keeps Northampton in the play-off places but dents Wasps' hopes of extending their season.
Northampton's rolling maul dominated throughout the contest and the home side were regularly penalised by Rose, with Wasps having players sin-binned on three separate occasions for illegally stopping a Saints drive, to leave Young frustrated.
"They were dominant up front, that was their one weapon," he said of Northampton. "They did not try and play, or need to play, any other way. You will always struggle to win any game if you cannot stop a driving line-out.
"We were better in the second half, but in the last 10 minutes I felt penalties would come from somewhere to put us inside our own 22.
"I had issue with quite a few (of those penalties), the last three in particular, but it does not change anything.
"It's no good me sitting here throwing stones at the referee. It doesn't change anything.
"We just have to move on, but everyone in the stadium never felt we were going to be allowed out of our half (in the last 10 minutes).
"It is hard enough to play Northampton with 15 players. There will always be yellow cards five yards from your own line but we had three penalties for driving line-outs being pulled down and there were no yellow cards there for them.
"But, make no bones about it, you have to stop driving line-outs, we were unable to do it and it was a big telling factor."
Saints rugby director Jim Mallinder was understandably more upbeat after the game and refused to apologise for his side's direct approach to the game.
"We would have been kicking ourselves if we had not have won but a team like Wasps can score points very quickly and we gave away too many penalties to allow them to keep the scoreboard ticking," he said.
"Our maul was exceptional and it was an area we targeted. Conditions can change and you have to have more to your game than that, but today the conditions were bad out there.
"It was blustery, it was snowing and if you have a weapon like that then why not use it?
"I thought David Rose refereed that part of the game particularly well, although I am sure Dai Young may say something else."