Newport Gwent Dragons coach Kingsley Jones expects his side will have to return to Sale Sharks in the last eight of the European Challenge Cup.
The Dragons lost out on top spot in Pool Two and a home quarter-final tie by losing 38-5 to Sale on Thursday.
But the two sides are set to face each other again at the AJ Bell Stadium based on the qualifying criteria.
"We have to be a lot better. We just didn't look ourselves at all," Jones told BBC Wales Sport.
"Do we come here with the same attitude again? We've learnt a lot about them and a little bit about ourselves.
"And there is a temptation to just draw a line under it but we can't do that. We can't be as inconsistent as we are."
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Sale finished two points clear of the Dragons at the top of the pool, with five wins and one defeat from their six games.
The Dragons are likely to qualify for the last eight as the runner-up with the best record, and that would see them play the pool winner with the third-best record, which is set to be the Sharks.
The English side lost away to the Dragons in the opening pool match after sending a weakened side to Rodney Parade, but they were a class above on Thursday as they scored five tries in a one-sided encounter.
|Qualifying criteria for the quarter-finals (ranking in brackets)|
|Best pool winner (1) v Third-best runner-up (8)|
|Second-best pool winner (2) v Second-best runner-up (7)|
|Third-best pool winner (3) v Best runner-up (6)|
|Fourth-best pool winner (4) v Fifth-best pool winner (5)|
"It wasn't a good performance," admitted Jones, who spent seven years as a coach at Sale.
"We really underperformed in a game we could have done a lot better. After the form we've had in this tournament, we expected more.
"I guess that motivation was with Sale. It showed. They needed to win. We struggled with our set-piece early on but we came to terms with it."
Harlequins and Gloucester are the other clubs to have secured a place in the quarter-finals, which will be played on 7-10 April.
The remaining places in the last eight will be known after the final pool games on Saturday. Cardiff Blues can join the Dragons if they collect five points against Calvisano and other results go their way.
How are the quarter-finals decided?
The five pool winners and three best-placed runners-up will qualify for the quarter-finals and will be decided as follows:
The pool winner will be the club with the highest number of match points in each pool. The best-placed runners-up will be the three clubs with the highest number of match points out of the five clubs that finish second in their respective pools.
For the quarter-finals, the pool winners will be ranked 1 to 5 and the best-placed runners-up 6 and 8 by reference to the number of match points earned.
Further details available on the European Professional Club Rugby website