To ensure that clubs will be able to select the strongest possible match day squads in the current circumstances, there was no limit to the number of players each club was permitted to register.

Subject to relevant union approval, the following players have been nominated to supplement each club’s tournament squad:

AGEN
Gael Doms (hooker), Zakaria El Fakir (prop), Théo Louvet (scrum half), Alexandre Odinga (wing)

BATH RUGBY
Jamie Bhatti (prop), Jaco Coetzee (back row), Jacques du Toit (hooker)

BENETTON RUGBY
Corniel Els (hooker), Nicola Piantella (second row)

CARDIFF BLUES
Efan Daniel (hooker)

CONNACHT RUGBY
Cathal Forde (out half), Oisin McCormack (back row)

DRAGONS
Dan Baker (back row), Gonzalo Bertranou (scrum half), Ioan Davies (full back/wing), Lennon Greggains (back row), David Richards (full back/wing), Ed Scragg (second row)

GLASGOW WARRIORS
Dylan Evans (prop), Cole Forbes (full back/wing), Ian Keatley (out half), Jordan Lenac (scrum half)

HARLEQUINS
Michele Campagnaro (centre/wing), Lewis Gjaltema (scrum half)

LEICESTER TIGERS
Nick Dolly (hooker), William Hurd (prop), Darryl Marfo (prop), Matias Moroni (centre/wing)

LONDON IRISH
Facundo Gigena (prop), Matt Williams (centre/wing)

MONTPELLIER
Louis Mauro (prop)

NEWCASTLE FALCONS
Mateo Carreras (wing), Cameron Nordli-Kelemeti (scrum half), Matias Orlando (centre), Jon Welsh (prop)

NORTHAMPTON SAINTS
Lewis Bean (second row), Oisin Heffernan (prop)

OSPREYS
Jordan Lay (prop), Ethan Roots (back row)

ULSTER RUGBY
James Humphreys (out half), Conor McMenamin (second row), Ben Moxham (centre), Jude Postlethwaite (centre), Harry Sheridan (back row)

ZEBRE RUGBY CLUB
Charles Alaimalo (flanker), Potu Junior Leavasa (back row/second row)

In advance of the resumption of the 2020/21 Challenge Cup, the 16 clubs which have qualified for the knockout stage of the tournament have registered their updated squads.