Fly half Madigan and tight head prop Ross are part of a heavyweight invitation side showing nine changes to the one beaten 28-14 by England on Sunday.

Head Coach Vern Cotter fields what may be the biggest pack in the club’s 127-year history, weighing in at a combined 945kg.

Giant Montpellier lock Paul Willemse has been added to the squad and starts in the second row with Argentina’s Patricio Albacete. Joe Tekori - a try-scorer against England - starts at six alongside Thierry Dusautoir and Facundo Isa. Ireland’s Mike Ross lines up with Corey Flynn and Pau’s Chris King in the from row.

The back line is full of Barbarians attacking flair. France’s Rory Kockott comes in at scrum half, Robbie Fruean and Waisea Nayacalevu are at centre, and Argentina's Horacio Agulla and Castres’ David Smith are on the wings.

The match is the last in Dusautoir’s glittering career, which has seen him lift Top 14 and European Cup titles, win 80 international caps and lead France a record 56 times.

But any send-off celebrations will be on hold for a while as the Barbarians aim to take their level of performance up another notch in their first meeting with Ulster since 1957.

Cotter said: "This is a very competitive and experienced group of Barbarians players and they felt they left a few tries out there at Twickenham. They are determined to impress against Ulster at the Kingspan Stadium and to live up to everything that goes with representing this historic club.”

Racing’s New Zealand flanker Chris Masoe is a late addition after a calf injury prevented Victor Vito from joining the squad in Belfast.