Former champions Toulouse, Saracens and last season's runners-up Racing 92 can take giant strides towards clinching qualification for the Champions Cup quarter-finals with fourth-round wins this weekend.
Racing On Inside Track
Racing 92 are unbeaten in the top-tier tournament this campaign and could all but secure a last-eight berth with a second victory in the space of a week over Leicester Tigers.
Threequarter Virimi Vakatawa says the club, bankrolled by multimillionaire Jacky Lorenzetti, is targeting home field advantage in the playoffs round.
The Parisians need to be one of four teams with the highest points at the end of the group stage to clinch a first knock-out tie at their La Defense Arena ground which opened in 2017.
"It's our main objective, so we will continue to work for that. It's going to be big to have a home quarter-final in front of our fans," he said. "We know we are on top. We have three more games left so we need to keep on working in order to keep on winning games to top our pool."
The France international crossed in last Sunday's end-to-end affair to bring his tally this term to nine tries -- the joint highest in European club rugby alongside Gloucester's Charlie Sharples.
Their back-line also include Ireland international Simon Zebo and Argentina winger Juan Imhoff, who have eight touchdowns, each as well as Scotland playmaker Finn Russell.
Saracens Back In The Chase
Winners in 2016 and 2017, the Saracens club is aiming for an eighth quarterfinal in as many years.
They are yet to lose this campaign and travel to the Cardiff Blues after a seven-try 51-25 thumping of the Welsh region in London last Sunday and will remain without England lock Maro Itoje who has a knee injury.
Elsewhere, Glasgow welcome already-eliminated Lyon with the tournament's joint-top scorer in flyhalf Adam Hastings, in good form since making his Scotland debut in June.
In a rerun of the 2004 final, Toulouse welcome Wasps to the Stade Ernest-Wallon with the French side on top of Pool 1 on 12 points after beating the English club 24-16 in Coventry last weekend.
A victory in France on Saturday would stretch Toulouse's unbeaten run across all competitions to nine games and put them firmly in the driving seat for a last-eight spot for the four-time champions after missing out last year.
Young full-back Thomas Ramos joins Hastings at the top of the points-scoring table, while France three-quarter Sofiane Guitoune tops the try-scoring chart on four and Wasps will also be wary of South Africa's Cheslin Kolbe who dotted down in a very impressive performance in the English Midlands.
Toulouse battles with Leinster for top spot in the group. The reigning champions welcome Bath to the Aviva Stadium after their fans were forbidden from taking flags into the Recreation Ground for health and safety reasons in the 17-10 win.
The Irish province will be without international center Robbie Henshaw with a hamstring injury, but can rely on world player of the year Johnny Sexton, who signed a contract extension until 2021 this week.
The two final rounds of the competition take place in January.
European Champions Cup fixtures this weekend (all times GMT/UTC):
Pool 4 Leicester v Racing 92 (1300)