London Irish, Saracens and hosts Harlequins have all named strong squads for the opening round of the JP Morgan Premiership Rugby Sevens.
While London Wasps have opted to use the competition to blood a number of their academy stars, their rivals will turn to their senior players.
Will Skinner, Ross Chisholm, Sam Smith (Harlequins), Kameli Ratuvou, Nils Mordt, Jackson Wray (Saracens), Ofisa Treviranus, Topsy Ojo, Shane Geraghty and Chris Hala'Ufia (London Irish) are among those taking part at the Stoop on Friday.
Wasps, on the other hand, will look Chris Mayor and rising stars Sam Jones and Matt Everard to lead their challenge.
The tournament will also see the clubs hand guest players and triallists a chances - with Louis Grimoldby (Quins), Derek Asbun, Sean Morris, Dan Wells (Wasps), Jono Ross (Saracens) and Michael Worrincy (London Irish) out to impress.
The top two teams from the pool will go through to the finals in Bath on August 6th.
Harlequins: 1 Dave Ward, 2 Will Skinner (capt), 3 Luke Wallace, 4 Sam Smith, 5 Ollie Lindsay- Hague, 6 Ross Chisholm, 7 Ben Botica, 8 Seb Stegmann, 9 Miles Mantella, 10 Henry Taylor, 11 Louis Grimoldby, 12 Jordan Burns
London Irish: 1 Alex Gray, 2 Ofisa Treviranus (capt), 3 Chris Hala'Ufia, 4 Shane Geraghty, 5 Tom Homer, 6 Topsy Ojo, 7 Michael Worrincy, 8 Gerard Ellis, 9 Darren Allinson, 10 Steven Shingler, 11 Luke Peters, 12 Conor Gaston
London Wasps: 1 Sam Jones, 2 Matt Everard, 3 Derek Asbun, 4 Jonah Holmes, 5 Jack Wallace, 6 Chris Mayor, 7 Sean Morris, 8 Danny Wells, 9 Liam O'Neil, 10 Will Robinson, 11 Mitchell Tamiau, 12 Jono Woodward
Saracens: 1 Jackson Wray, 2 Jono Ross, 3 Will Fraser, 4 George Kruis, 5 Duncan Taylor, 6 Ali Price, 7 Ben Spencer, 8 Nils Mordt (capt), 9 Kameli Ratuvou, 10 James Short, 11 Nathan Earle, 12 James Stephenson.
Fixtures - Game 1 (7.30pm): London Irish v Harlequins
Game 2 (7.55pm):London Wasps v Saracens
Game 3 (8.25pm): London Wasps v London Irish
Game 4 (8.50pm): Harlequins v Saracens
Game 5 (9.20pm): London Irish v Saracens
Game 6 (9.45pm): London Wasps v Harlequins