Flyhalf Tim Swiel scored seven points to help Harlequins beat English Premiership champions Saracens 17-10 on Saturday.
Swiel contributed two conversions and a penalty goal in the first half. Harlequins dominated the early exchanges, and went to the break with a 17-0 lead.
Saracens, who boasted South Africans such as Brad Barritt, Schalk Brits, Petrus du Plessis and Michael Rhodes in their starting side, fought back in the second stanza. It was not enough, however, as Harlequins limited the visitors to just seven points in that period.
Meanwhile, Wasps, who had Ashley Johnson in their ranks, picked up a valuable away win against Nic Groom's Northampton Saints. The result saw Wasps moving to the top of the English Premiership log.
Wynand Olivier was in action for the Worcester Warriors in their match against the Sale Sharks on Saturday. The former Springbok and Bulls centre scored a try for the hosts, but Sale came back strongly to force a 34-34 draw.
Leicester will host Bath on Sunday.
ROUND 4 RESULTS
Bristol 17 Exeter 41
Gloucester 13 Newcastle Falcons 18
Harlequins 17 Saracens 10
Northampton Saints 20 Wasps 15
Worcester Warriors 34 Sale Sharks 34
Photo: Joel Ford/Getty Image