Stand-off Joseph Paulo has been arguably the stand-out player at the tournament so far, and his half-back pairing with Craig Priestly has been a key reason for the Tomahawks success so far.
They welcome back hooker Andrew Henderson, who has sat out both games so far, in place of brother Ian at hooker.
North Queensland centre Kane Linnett is also missing for the Scots.
Scotland squad: Danny Addy (Bradford), Sam Barlow (Halifax), Danny Brough (Huddersfield), Brett Carter (Workington), Luke Douglas (Gold Coast), Dale Ferguson (Huddersfield), Ben Fisher (London), Ben Hellewell (Featherstone), Andrew Henderson (Sheffield) Alex Hurst (London), Ben Kavanagh (Widnes), Brett Phillips (Workington), Matthew Russell (Gold Coast), David Scott (Featherstone), Mitchell Stringer (Sheffield), Alex Szostak (Sheffield), Adam Walker (Hull KR), Peter Wallace (Brisbane), Oliver Wilkes (Wakefield)
USA squad: Bureta Faraimo (Mackay), Kristian Freed (Connecticut), Michael Garvey (Ipswich), Roman Hifo (Mangere), Daniel Howard (Wentworthville), Stephen Howard (Tuggeranong), Judah Lavulo (Cabramatta), Haveatama Luani (Wests), David Marando (Belrose), Clint Newton (Penrith), Mark Offerdahl (Connecticut) Joseph Paulo (Parramatta), Matthew Petersen (Cudgen) Edward Pettybourne (Wests), Craig Priestly (Southampton), Tuisegasega Samoa (Redcliffe), Matthew Shipway (Newcastle South), Les Soloai (Utah), Taylor Welch (New York)