Those three teams have already clinched their places in the knock-out phase having guaranteed top spot in their respective Pools with one round still to play.
Toulouse (Pool 5) and Leinster Lions (Pool 4) are the only two teams with 100% records after Round 5, while Leicester Tigers (Pool 1) are unbeaten having drawn their opening game at Neath.
If these three teams go on to win their final Pool matches this weekend - Leicester Tigers host Neath at Welford Road on Saturday, while Leinster Lions travel to Bristol Shoguns and Toulouse travel to London Irish on Sunday - then they will claim three of the four home matches in the quarter-finals.
The six Pool winners will be joined in the quarter-finals by the two best runners-up. In the event of teams - be it two or three - in the same Pool being level on match points the Pool winners and rankings will be determined after taking into account the results of only those matches between the tied teams (i. match points; ii. tries scored; iii. points difference).
The two best placed runners-up will be determined by the following criteria - i. Match Points; ii. Tries scored in all Pool matches; iii. Points difference in all Pool matches; iv. Fewest number of players sent off in Pool matches; v. The toss of a coin.The eight qualifiers will be ranked by the above criteria and the draw for the quarter-finals will be:
TEAM 1 v TEAM 8; TEAM 2 v TEAM 7;
There are six other teams who could reach eight points - Munster and Perpignan in Pool 2, Bourgoin in Pool 3, Bristol Shoguns in Pool 4 and both Biarritz Olympique and Ulster in Pool 6.