They are two big losses against a mis-firing Wigan side. There was also talk about Own and Ryan struggling and with Catalan at home 6 days after, who are not travelling well and have key injuries themselves, i'd be very tempted to leave them out and get them closer to full fit fitness. I'd go
Hall
Johnstone
Collis
Arundal
Riley
Miller
Sammut
Scruton
Washbrook
D Smith
Lauitiiti
Crowther
Griffin
McShane
Simon
Hand
Trout