Stormers fly-half Grant is looking to wrestle the No10 shirt from current incumbent Ruan Pienaar, or at least aiming to be included among the replacements now that Bath's Butch James has been ruled out of the series and Francois Steyn is considered a major doubt.
Hooker Brits is also with the Stormers and will therefore not be playing in the Super 14 semi-finals, meaning his performances for the Babaas could be a real opportunity to persuade de Villiers to select him over Bismarck du Plesiss and John Smit in Springbok colours.
The same can be said for Botha. De Villiers has made it clear that he will only select overseas players if absolutely necessary, making the Ulster prop's task of breaking back into the South African squad that much harder.
While Grant, Brits and Botha are all hoping to play a part against the Lions this summer, the star-studded Barbarians squad also includes a number of players who have faced the Lions on previous tours.
Doug Howlett, Justin Marshall, Luke McAllister, Jerry Collins, Chris Jack and Greg Somerville all featured for New Zealand against the Lions four years ago, while Seilala Mapusua played for Otago on the same tour and Justin Harrison starred for Australia in 2001.
Former Lions Corry and Lewsey will be making their last appearances as professionals having announced their retirements earlier this season.
The pair both toured with the Lions under Sir Clive Woodward in 2005, as did D'Arcy and Murphy, with Corry and Balshaw having been part of the 2-1 series loss to the Wallabies four years earlier.
There is also a Lions flavour to the Babaas coaching staff as triple tourist Dai Young takes the reigns. The 1989, 1997 and 2001 Lion will be assisted by Mike Catt, a team-mate of Young's from his last two Lions tours.
"I'm delighted with the squad that's been selected and I'm looking forward to working with them and London Irish assistant coach Mike Catt when we meet up on May 26," said Young.
"The squad is full of quality players, including a number of Rugby World Cup, Tri-Nations and Grand Slam winners and I'm expecting them to give a very good account of themselves when they play England and Australia."
Backs: Iain Balshaw (Gloucester Rugby and England), Ben Blair (Cardiff Blues & New Zealand), Gordon D'Arcy (Leinster and Ireland), Peter Grant (Stormers and South Africa), Doug Howlett (Munster & New Zealand), Josh Lewsey (London Wasps and England), Seilala Mapusua (London Irish & Samoa), Justin Marshall (Saracens and New Zealand), Luke McAllister (Sale Sharks and New Zealand), Geordan Murphy (Leicester Tigers & Ireland), Sonny Bill Williams (Toulon), Dimitri Yachvilli (Biarritz Olympique & France)
Forwards: Serge Betsen (London Wasps & France), BJ Botha (Ulster & South Africa), Schalk Brits (Stormers and South Africa), Sebastien Bruno (Sale Sharks & France), Jerry Collins (Toulon & New Zealand), Martin Corry (Leicester Tigers & England), Rocky Elsom (Leinster & Australia), Justin Harrison (Bath Rugby & Australia), Chris Jack (Saracens & New Zealand), Greg Somerville (Gloucester Rugby & New Zealand), Iestyn Thomas (Scarlets & Wales), Paul Tito (Cardiff Blues)