STEVE Clarke makes four changes to the team that lost 3-2 at Reading in the Barclays Premier League on Saturday.
Boaz Myhill, Gabriel Tamas, Goran Popov and Markus Rosenberg earn starting berths.
The men to make way are benched trio Ben Foster, Jonas Olsson and Liam Ridgewell and skipper Chris Brunt, who misses out altogether due to illness.
Steven Reid returns from a seven-game absence due to a shin injury to take his place among the substitutes, where he is joined by fit-again Peter Odemwingie.
James Morrison captains the side, while the cup replay comes too soon for Shane Long (dead leg), Claudio Yacob and Marc-Antoine Fortune (both hamstring).
Harry Redknapp makes six changes to the Rangers side that fought out a goalless league draw with Tottenham at the weekend.
Rob Green, Anton Ferdinand, Tal Ben Haim, Alejandro Faurlin, Jay Bothroyd and Djibril Cisse come in.
The men to make way are benched trio Stephane Mbia, Shaun Wright-Phillips and Adel Taarabt, as well as Julio Cesar, Ryan Nelsen and Fabio, who are left out altogether.
Former Baggies striker Rob Hulse is among the substitutes for the Hoops.
ALBION (4-4-2): Myhill; Jones, McAuley, Tamas, Popov; Dorrans, Thorne, Morrison, Thomas; Rosenberg, Lukaku. Subs: Foster (gk), Reid, Odemwingie, El Ghanassy, Dawson, Ridgewell, Olsson.
QPR (4-5-1): Green; Onuoha, Hill, Ferdinand, Ben Haim; Mackie, Faurlin, Derry, Park, Bothroyd; Cisse. Subs: Murphy (gk), Taarabt, Wright-Phillips, Ephraim, Ehmer, Hulse, Mbia.
REFEREE: M Atkinson (West Yorkshire).