Mike Ruddock admitted the high penalty count and two yellow cards killed his team's hopes as Worcester Warriors lost 38-5 to Leicester Tigers in the Guinness Premiership at Welford Road.
Worcester were on the wrong end of a high penalty count and were forced to play half the second half with 14 men after Pat Sanderson and Aleki Lutui were both sin binned.
Director of Rugby Ruddock conceded that ill discipline had played major part in the league defeat and admitted his team needed to make amends in the coming weeks.
"When you have a penalty count of 17-7 and two boys in the bin it is going to be a long game," said Ruddock. "There were bags of effort but we weren't precise and our lack of discipline killed us.
"Away from home you want to be in the right areas and we used the wind well in the first half. We didn't want to be chasing the game in the second half.
"We wanted to be level pegging or certainly not chasing the game. We took the wind and went for the corners and missed a kickable penalty.
"We had some try scoring opportunities in the first half. Marcel Garvey twice went down the left wing and if we could have nailed one of those by half-time it would have been a very different story.
"But in the end the penalty count, our ill discipline and their efficiency at the breakdown gave us this result."
Warriors showed great resilience in the opening 20 minutes of the match but two quick-fire tries left them chasing the game.
"The first 20 minutes was okay, we used the wind well and out tactics were good. We pressed in behind them and put the pressure on them.
"At that stage I thought things were going well but then they broke away and got a try and then got another very quickly.
"I was disappointed we kicked short after the first try, we gave them chance to group as they wanted and come at us for a second try.
"The breakdown was also very efficient for them. They certainly beat us in that area, there is no doubt about that, and in the second half to lose two men to the sin bin put us under."
Both teams were hit for a succession of penalties in the scrum and Ruddock admitted it had been a cause for concern with a French referee in charge.
"It was a difficult situation with the referee and the communication when we wanted to iron out some of the problems," added Ruddock.
"The penalty count suggests that we were at fault for the problems at the scrum, I don't know why that is because we pride ourselves on a strong scrum.
"On a couple of occasions he picked up Leicester for not binding but it just seemed to be that a lot of scrums ended up on the floor or penalties. I don't know if that we a communication difficulty but it didn't seem to be managed as well as other games.
"But I have no problem with cross border referees, we have had them in Europe and they have been fine. The only one concern is when you do have a few difficulties you have to make sure the communication is right."
Warriors will take a one-point advantage back to Sixways after a Niall Annett try on the stroke of full-time handed Dean Ryan's men victory in the first leg of the Greene King IPA Championship play-off final.