The Demons finalised their side on Friday evening, naming Miller, Warnock and Addam Maric as their emergencies.
Joel Macdonald, Tom Scully, Jordie McKenzie and Spencer have been named on the interchange.
On Thursday, defender Kyle Cheney and speedster Jamie Bennell were included, although young-gun Cale Morton was omitted. Cheney will play his first match this season.
Morton has made five appearances this season, after missing the early part of 2010 with a knee injury, which he sustained in the NAB Challenge.
Bennell was a traveling emergency against Adelaide at AAMI Stadium last round.
Skipper James McDonald, who was ruled out earlier in the week, will also be sidelined for his third consecutive game, as he continues to battle a hamstring injury.
Cheney, who debuted in round one against North Melbourne last year and played 12 matches in 2009, has been right on the cusp this season.
He has often been named as an emergency and has been among Casey’s best performers in the VFL this season.
Defender Jared Rivers will reach a personal milestone this round, lining up in his 100th AFL match.
It’s a fine effort from Rivers, considering he endured a frustrating run with injury in 2007-08, after winning the 2004 NAB AFL Rising Star.
Round 14 team v St Kilda
HB: Colin Garland, Jared Rivers, Jack Grimes
C: Brad Green, Jack Trengove, Cameron Bruce
HF: Jamie Bennell, Matthew Bate, Lynden Dunn
F: Neville Jetta, Jack Watts, Aaron Davey
FOLL: Mark Jamar, Brent Moloney, Nathan Jones
I/C: Joel Macdonald, Tom Scully, Jordie McKenzie, Jake Spencer
In: Cheney, Bennell, Spencer
Out: Morton, Miller, Warnock