Last week’s victory over Danish side Silkeborg made it a perfect five wins from five in the group stage of the Europa Conference League and secured top spot with a game to spare.
As a result, Moyes has left the bulk of his first-team behind in London ahead of the trip to Bucharest, with a number of squad players and academy graduates featuring.
The likes of Alphonse Areola, Manuel Lanzini and Angelo Ogbonna are all involved having been regulars in the competition, while summer signing Nayef Aguerd starts after making his long-awaited competitive debut against Silkeborg.
Elsewhere, 16-year-old midfielder Ollie Scarles, an unused substitute in Anderlecht last month, makes his debut, as does England U18 striker Divin Mubama.
Fellow teenager Freddie Potts, one of several academy youngsters who featured in a dead-rubber against Dinamo Zagreb this time last year, is among those on the bench.
West Ham XI: Areola; Coufal, Aguerd, Ogbonna, Johnson, Scarles, Lanzini, Coventry, Downes, Fornals, Mubamba
Subs: Randolph, Hegyi, Ashby, Casey, Clayton, Forbes, Swyer, Orford, Potts, Appiah-Forson