Leicester skipper Toby Flood admitted his side did not deserve a bonus point after their 34-3 win over Treviso on Friday.
The Tigers delivered an error-strewn showing at Welford road and only secured a vital bonus point thanks to an 80th minute try by wing Adam Thompstone.
"We made too many errors, again," said Flood after the match.
"If we qualify from our pool, we will look back and think we got five points which were important.
"But it's such an odd environment to take five points and play as poorly as that. We did not deserve it.
"There's no rhythm at the moment, no continuity. We are making too many errors and every time we get any momentum we turn the ball over.
"It has been frustrating to say the least. We did not expect to come in at half-time any more than that (13-0) because of the way we played.
"Credit to the guys for scoring three tries in the second half. They came here to shut up shop and make life difficult for us and we made life harder for ourselves."
The England fly-half admitted Leicester would have to show dramatic improvement by the time they face Montpellier in back to back matches in December.
"We need to raise our game massively in terms of the last five or six games," he added.
"We have just done enough and just been getting by, which is not acceptable for us.
"I am a huge part of it, I am captain of the side and I have to manage that.
"We will deal with it. There's a lot of disappointed guys in that changing room.
"The rain wasn't ideal but you can't blame the conditions. There were set piece errors, handling errors, continuity mistakes, all sorts of things.
"It's really disappointing. All of us can be better."