Midfielders Williams and Kalala, both deadline day signings from Bristol City and Yeovil respectively, are hoping to play some part.
Williams is on loan until the end of the season, while Kalala has signed a short-term deal until June 30.
Penney may also play Peterborough forward Rene Howe and Reading midfielder Scott Davies after the pair joined the npower League One side on loan last week.
Rovers have no fresh injury concerns, but are blighted by suspension to two key players, with midfielder Chris Lines and defender Danny Coles both missing out.
Source: PA
Source: PA