Centres Anthony Allen and Mike Tindall have recovered from shoulder and calf injuries respectively, while winger Mark Foster has overcome a groin problem.
The starting pack is exactly the same as the one that began against Llanelli last weekend which means Nick Wood starts at loosehead prop alongside Mefin Davies at hooker and Califano at tighthead.
Bortolami is joined by Alex Brown at lock, while Peter Buxton, Andy Hazell and James Forrester complete the back row.
But Balshaw, who switched to Kingsholm from Leeds in the summer, is relishing the chance to meet his former club on the opening day of the season.
"It will be a fantastic occasion," Balshaw said. "They are two teams with deep and proud histories behind them and the atmosphere will be fantastic.
"It will be nice to run out at Kingsholm with the Shed on my side for the change. We are expecting fierce competition because these really are huge games and the reason why we play rugby.
"Everyone in the squad is looking forward to it immensely. These are the games you remember above all others and it should be a great occasion."
Gloucester's bench is broken down into a 4/3 forward split. Olivier Azam, Jack Forster, Will James and Luke Narraway are the forward options, while Rory Lawson, Ludovic Mercier and Rudi Keil cover the back possibilities.
GLOUCESTER (v Bath, tomorrow, 3pm): Olly Morgan; Iain Balshaw, Mike Tindall, Anthony Allen, Mark Foster; Willie Walker, Peter Richards; Nick Wood, Mefin Davies, Christian Califano, Marco Bortolami (capt), Alex Brown, Peter Buxton, Andy Hazell, James Forrester. Reps: Olivier Azam, Jack Forster, Will James, Luke Narraway, Rory Lawson, Ludovic Mercier, Rudi Keil.