Niko Matawalu's two-try cameo fired England a World Cup warning as Fiji dispatched Canada 47-18 at The Stoop.
The Bath-bound scrum-half bossed Fiji's fluent, potent back line under the shadows of Twickenham, 13 days before the Pacific Islanders will look to spoil England's World Cup party.
Matawalu limped off gingerly just before half-time with a leg injury, but was clearly removed as a precaution and under little panic.
The 26-year-old's class is underscored by his ability to stand out as Fiji's biggest threat even in a back line dripping with strike runners and match-winners.
Watching coaches Stuart Lancaster and Andy Farrell were left in little doubt as to who will pose them the greatest threat when England open their World Cup campaign against Fiji a week on Friday.
Matawalu sparked Fiji's try glut, his second securing three for Fiji in the first half.
Stade Francais wing Waisea Nayacalevu claimed a brace of his own, with Metuisela Talebula adding a fifth and monster wing Nemani Nadolo slotting a perfect 22 points from the tee.
Canada hit back with tries from Conor Trainor and a late brace from Phil Mackenzie as Fiji tired and fell off the pace.
England open their Pool A account by taking on Fiji at Twickenham on September 18, desperate for a victory to set the tone for their group-of-death battle.
Only two teams can progress to the quarter-finals, leaving powerhouses England, Wales and Australia all fearing an early exit.
Fiji are keen to muscle in on that last-eight argument themselves, and would love nothing more than to shock the hosts at the top of the tournament.
Lancaster and Farrell will come away from The Stoop cemented in the belief that the keys to victory against Fiji will lie wholly in suffocating the Islanders in structure.
Stymie Fiji up front, deny their talent-laden back line any front-foot ball, and England will secure the win they so crave; Allow Matawalu to feed steamroller flyers Nemani Nadolo, Vereniki Goneva and Nayacalevu and England could be in trouble.
Giant Canterbury Crusaders wing Nadolo, standing 6ft 5in and tipping the scales at 20 stone, is among the biggest Test-match specimens.
England wings Jonny May and Anthony Watson boasts bagfuls of guile, but will need all their wits to bring down the 27-year-old in full flight.
Fiji captain Akapusi Qera unleashed several hefty hits, a custom often greeted with a chuckle from the Montpellier flanker, that England's back row can expect to experience in full force.
Canada were hardly able to offer any authority, and Ireland boss Joe Schmidt can be forgiven for feeling he learned little from this encounter.
Ireland will open their Pool D campaign by facing Canada in Cardiff on September 19, but already know full well Clermont enforcer Jamie Cudmore is the lynchpin.
Canada struggled to release Scarlets-bound wing DTH Van der Merwe, Fiji denying the North Americans any real foothold.
Ireland will look to do the same, but Cudmore's impending battle with Paul O'Connell could be a sight to behold.