Russell, 34, joined from Bristol City on a month-long loan deal on transfer deadline day but was not involved in the 2-2 draw at Leyton Orient on Saturday.
He will start at Kenilworth Road though while teenage winger Alex Dyer is also primed for a start after starring in the Carling Cup defeat at Middlesbrough last week.
Left-back Danny Jackman remains sidelined with his medial knee ligament injury while midfielder Giles Coke is a long-term absentee with a knee injury of his own.
Competition rules which state that sides must play at least six of their top appearance makers mean that Gray is unable to make many changes as his side seek their first away win of the season.
Luton boss Kevin Blackwell is expected to rest his key players for the clash.
The Kenilworth Road chief will make full use of his squad for the southern section first-round clash, as he has one eye on Saturday's League One fixture against Bristol Rovers.
Blackwell is likely to rest one of his centre-backs, Chris Coyne or Chris Perry, while midfielder Matthew Spring, winger Darren Currie and forward Paul Furlong should also be left out of the starting XI.
Blackwell will definitely be without midfielder Dave Edwards, who has been included in the Wales Under-21 squad for their European Championship qualifier against France on Friday.
Defender Richard Jackson (groin), midfielder Richard Langley (knee) and forward Sam Parkin (ankle) remain sidelined.
Sporting Life