John Ward's first game in charge saw Rovers come from behind twice to draw at Aldershot, ending a run of three straight defeats that led to the sacking of Mark McGhee.
But the point was soured with the loss of midfielder Paterson and forward Clarkson to injury.
Paterson lasted just 18 minutes before going off with a hamstring problem while Clarkson took a knock to the ankle in the second half.
It comes as a further blow to Ward who is already without injured quartet Matt Gill, Adam Virgo (both knee), Matt Harrold (cruciate ligament) and Scott Bevan (wrist).
To make matters worse, Cian Bolger, Tom Eaves, Matthew Lund and Sam Walker's loan deals expire in January.