O'Callaghan gets Baa-Baas call
Ireland lock Donncha O'Callaghan is one of four players added to the Barbarians' 24-man squad to face England on June 1.
France fly-half Francois Trinh-Duc, South Africa second row Juandre Kruger and Argentina full-back Juan Martin Hernandez are among the other international heavyweights named in head coach Dean Ryan's side at Twickenham.
Nine nations are represented, with New Zealand boasting six players in the squad, while 19 men are set to wear the famous black and white hooped shirt for the first time in an experienced group that boasts a combined 730 international caps.
Ryan said: "It is a testimony to the special appeal the Barbarians has throughout the rugby world that we have been able to bring together such an experienced and talented squad of players.
"It's a privilege to be able to work with a group who have achieved so much and we're looking forward to taking on a young England side at Twickenham next Sunday."
There is one change to the group of players previously announced with Castres-bound All Black Sitiveni Sivivatu now unavailable.
Backs: Jimmy Cowan (Gloucester & New Zealand), Tomas Cubelli (Belgrano & Argentina), Hosea Gear (Toulouse & New Zealand), Juan Martin Hernandez (Racing Metro & Argentina), Brock James (Clermont), James O'Connor (London Irish & Australia), Rene Ranger (Montpellier & New Zealand), Joe Rokocoko (Bayonne & New Zealand), Benson Stanley (Clermont & New Zealand), Francois Trinh-Duc (Montpellier & France).
Forwards: Julien Brugnaut (Racing Metro & France), Schalk Ferreira (Toulouse), Mamuka Gorgodze (Montpellier & Georgia), Andrew Hore (Highlanders & New Zealand), Juandre Kruger (Racing Metro & South Africa), Alexandre Lapandry (Clermont & France), Juan Manuel Leguizamon (Lyon & Argentina), Nahuel Lobo (Montpellier & Argentina), Donncha O'Callaghan (Munster & Ireland), Ti'i Paulo (Clermont & Samoa), Sona Taumalolo (Perpignan & Tonga), Joe Tekori (Toulouse & Samoa), Roger Wilson (Ulster & Ireland), Davit Zirakashvili (Clermont & Georgia).