Twickenham plays host to the final World Series Sevens event of the season this weekend, with Fiji on the verge of picking up the overall title.
Ben Ryan's side lead the series standings by 14 points from South Africa, who are the only nation capable of stopping the Fijians from claiming the title for the second year running.
The remainder of the teams will be using the two-day event as part of their build-up for the Rio Olympics, or the upcoming repechage event which will determine the final Olympic qualifier.
Fiji handed tough draw with series title on the line
Following defeat in last weekend's Paris Sevens final against the Samoans, Fiji landed in Pool B for the London tournament, alongside Australia, England and Wales.
Hosts England will be up for the challenge of meeting the first and fourth ranked sides this season, before bringing the curtain down on Saturday's action against rivals Wales. With just two teams able to qualify for Sunday' cup quarter-finals, the scrap for positioning in Pool B will be a fascinating watch on the opening day's play.
Samoa's reward for winning in Paris last weekend is a spot in Pool A, where they will face South Africa, Canada, and last year's winners at Twickenham, the United States.
Kenya will face three European sides in Pool C in the form of France, Scotland and Portugal, while Argentina, New Zealand, Russia and Brazil are set to battle it out in Pool D.
Hayne's Sevens bombshell leads Twickenham team news
Former NRL and NFL player Jarryd Hayne has been named in Fiji's 12-man squad for this weekend, less than a week after turning his attention to Sevens. Having announced his retirement from the San Francisco 49ers last Sunday, Hayne has now been handed the opportunity to press home his case for a spot in the Olympic team and to quieten the doubters.
Hosts England have bought Tom Mitchell, Dan Norton and Marcus Watson into their squad, while France include Virimi Vakatawa who lit up the Paris Sevens last weekend.
Another man making his season debut at Twickenham is Juan Imhoff of Argentina. One of the best wingers on the planet in the 15-a-side game, Imhoff joins Santiago Cordero in an Argentinian squad which will hope to continue thier strong recent form.
New Zealand welcome back Tim Mikkelson to the fold after missing a couple of tournaments through injury, and he joins a 12-man squad which includes Akira & Reiko Ioane, and also Sonny Bill Williams.