Harlequins' head of rugby Paul Gustard bemoaned his side's failure to take their opportunities in their 28-15 defeat at Bristol Bears.
Two tries from Luke Morahan, a score from Chris Vui and 13 points from the boot of Callum Sheedy ensured Bristol made history at Ashton Gate as they secured five consecutive league wins.
Aaron Morris and Gabriel Ibitoye scored tries for Harlequins, while Brett Herron kicked a penalty and Marcus Smith added a conversion.
But it was Quins’ lack of ruthlessness that left Gustard disappointed.
"We had 70 per cent of the possession in the second half but blew chance after chance,” he said.
“They were clinical in taking theirs in the first half, but overall our defence was excellent as we limited the league's best game-breaker, Charles Piutau, to very little.
"Unfortunately our set-piece didn't function - last week against Exeter we set the benchmark but today was the polar opposite."
After a disappointing first-half performance from fly-half Brett Herron he was replaced at the interval by Marcus Smith, whose efforts rejuvenated his side.
"Brett missed a couple of kicks and it wasn't his day,” he added.
“We didn't pick Marcus in the starting line-up as he hasn't been able to train all week but he was electric when he came on."
Bristol's director of rugby Pat Lam said: "The boys have every right to be proud of their achievement but the second half was very frustrating as we had a long spell to pick up the bonus point which we wanted, but didn't get.
"We had four wins from four matches but in training this week there was an element of looseness, so we knew we needed to have the impetus to start well, and we certainly did that.
"However, the second half was not a great advert for rugby as it was so slow. We were not accurate enough and became sloppy but we did show some great defence."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article