Gatland is due to name his first Lions team tomorrow but Baa-Baas boss Dai Young has announced his own matchday 23 this morning.
Young, who is a triple Lions tourist and featured on the two most recent trips to Australia in 1989 and 2001, has selected a squad packed with international talent for the maiden meeting between the sides.
Italian captain Sergio Parisse leads the team from No8 as Young opts for a starting XV made up of four New Zealanders, two Englishmen, two Americans, two South Africans, two Italians, a Frenchman, a Welshman and an Australian.
Wales prop Paul James and Wasps' uncapped English duo Eliott Daly and Sam Jones provide the Home Nations presence, with 2009 Lion James Hook named alongside fellow Welshman Duncan Jones, Scotland's Jim Hamilton and England Word Cup winner Mike Tindall among the replacements.
Harlequins playmaker Nick Evans will pull the strings at fly-half alongside Biarritz veteran Dmitri Yachvili, with Munster's former Cardiff Blues and All Blacks star Casey Laulala starting alongside Daly in midfield.
Ulster's Jared Payne is picked at full back, with speedsters Taku Ngwenya and Joe Rokocoko chosen on the wings.
James is joined in the front row by Saracens' South African hooker Schalk Brits - who missed out on facing The Lions in 2009 having just agreed a move to London - and Leicester's departing Italian prop Martin Castrogiovanni.
Dean Mumm starts alongside Marco Wentzel in the second row, with the former having a point to prove after leaving his native Australia for Exeter earlier this season having been told that he had little chance of squaring up to The Lions with the Qantas Wallabies.
Parisse is joined in the back row by Northampton's hugely physical American Samu Manoa and 21-year-old Jones, with Leonardo Ghiraldini, Imanol Harinordoquy, Andrea Lo Cicero and Khan Fotuali'I completing the line up from the bench.
Barbarians team to face The Lions
Jared Payne (Ulster); Joe Rokocoko (Bayonne and New Zealand), Elliot Daly (London Wasps), Casey Laulala (Munster and New Zealand), Takudzwa Ngwenya (Biarritz and USA), Nick Evans (Harlequins and New Zealand), Dimitri Yachvili (Biarritz and France); Paul James (Bath and Wales), Schalk Brits (Saracens and South Africa), Martin Castrogiovanni (Leicester and Italy), Marco Wentzel (London Wasps and South Africa), Dean Mumm (Exeter Chiefs and Australia), Samu Manoa (Northampton and USA), Sam Jones (London Wasps), Sergio Parisse (Stade Francais and Italy, captain)
Replacements: Duncan Jones (Ospreys and Wales), Leonardo Ghiraldini (Treviso and Italy), Jim Hamilton (Gloucester and Scotland), Imanol Harinordoquy (Biarritz and France), Andrea Lo Cicero (Racing Metro and Italy), Kahn Fotuali'i (Ospreys and Samoa), James Hook (Perpignan and Wales), Mike Tindall (Gloucester and England)