American Rossi will still participate in FP1 for the team, but will then hand over to Chilton for the rest of the weekend.
The team announced late on Thursday that Chilton would not compete, and that 22-year-old Rossi would therefore step in for his F1 race debut while the team attempted to resolve the situation as quickly as possible.
Chilton subsequently released a statement through his PR company saying that he had volunteered to move aside for the 2014 Formula 1 Shell Belgian Grand Prix.
On Friday morning, however, the team formally applied to change their nominated driver from Rossi back to Chilton for this weekend's race. The request was approved by the stewards.
Marussia also requested that Rossi stay in the car for FP1, which was also approved.
Chilton will therefore make his 31st Grand Prix start with the team on Sunday.