London Irish is in an Aviva Premiership relegation scrap with the Newcastle Falcons, so both sides will need their New Zealand contingent firing for them in the coming weeks.
The Exiles scored a crucial 23-18 win over Gloucester on the weekend.
Former Highlanders prop Halani Aulika scored an early try, while fullback Sean Maitland and former Auckland lock William Lloyd also featured. For Gloucester, John Afoa and Jeremy Thrush were in the pack, while fullback Tom Marshall was yellow-carded.
Thomas Waldrom's Exeter Chiefs are at the top of the log after a 20-12 win over Northampton, for whom wing Ken Pisi scored a try. His brother George Pisi was also in the starting line-up, as was wing Ahsee Tuala.
Jimmy Gopperth was among the points again for Wasps in their 39-12 defeat of Sale. The No 10 scored 19 points, including a try, while centre Charlie Piutau also dotted down. Sale's Johnny Leota received a 73rd minute yellow card.
Leicester Tigers, with Mike FitzGerald, Jono Kitto and Telusa Veainu in the mix, beat Saracens 21-13.
Bryce Heem's Worcester edged Harlequins 21-15. Ben Botica tried to keep Quins in the contest with five penalty goals, while Mat Luamanu appeared at blindside flanker.
Mike Delany kicked five goals for Newcastle but it was not enough as Bath defeated the Falcons 21-19.
There were two catch-up Guinness PRO12 matches. Cardiff Blues beat Munster 37-28 for the first time in seven years, with Rey Lee-Lo marking Francis Saili. Isa Nacewa kicked two penalty goals for Leinster, who went down 12-6 to Grayson Hart's Glasgow Warriors.
In the French Top 14, Montpellier inflicted a crushing 60-7 defeat on high fliers Racing-Metro, who were minus Dan Carter, though not Chris Masoe, Joe Rokocoko and Ben Tameifuna.
A try to No 6 Steven Setephano helped Grenoble beat Brive 26-22, while Clermont - starting Isaia Toeava and Fritz Lee - won 32-23 over Toulouse, who had hooker Corey Flynn in their starting XV.
Colin Slade kicked six penalty goals as his Pau club edged Castres 21-16. David Smith copped a yellow card for the latter.
Embattled Oyonnax had a narrow 30-28 win over Agen, for whom wing George Tilsley scored a try.
Paul Williams scored a key late try to assist Stade Francais to a 33-20 win over La Rochelle. Alde de Malmanche appeared off the bench for Stade, while Jason Eaton and Hikairo Forbes started for La Rochelle.
Milton Haig's Georgia won the European Nations Cup with a 38-9 victory over Romania, cementing a four-year unbeaten record in that competition.