He scored 19 tries last season for the Bulls and tomorrow will form a back-three alongside Mark Foster, who returns after a foot injury and full-back Olly Morgan.
"We see this is a great opportunity to give Karl another 80 minutes in a competitive environment so we can gauge where he is at," head coach Dean Ryan told www.gloucesterrugby.co.uk
"He is a tremendously exciting prospect but after this game we will have a clearer view of where he needs development. He has fitted into the group really well and now we want to see him at this level of competition.
"I think it is great for Karl because he has waited for this opportunity for a long time and really wants to make an impression."
Gloucester can still qualify for the knockout stages of the competition but they not only require a victory against Bath but a favour from Bristol, who travel to group leaders the Ospreys.
However, Ryan has named an experienced and competitive side for their second west country derby in the space of a week.
Mike Tindall will skipper the side in the centre alongside Jack Adams, while Willie Walker and Haydn Thomas get another opportunity to forge their half-back partnership.
"Mike's experience and attitude are fantastic qualities to have around the squad - he is a great leader and can get the best out of those around him," Ryan said. "We will need his qualities in the coming weeks and tomorrow will be a test of that against Bath."
Although there are changes up front, Ryan is able to call on plenty of quality in his forward unit. Patrice Collazo comes in at loosehead in place of Nick Wood, Rob Elloway will start his first competitive game of the season at hooker and Italian international Carlos Nieto starts at tighthead.
There are two changes at lock, where Jonathan Pendlebury and Will James start, while Jake Boer reverts to the blindside flank, James Merriman has recovered from a groin injury to start in the number seven shirt and Adam Balding is at eight.
On the bench, Jack Forster and Ross McMillan are the front row replacements and they will be joined by lock Alex Brown, scrum-half Rory Lawson, winger James Simpson-Daniel and stand-off Brad Davies.
Ryan will make a decision tomorrow on whether Adam Eustace or Andy Hazell will be named as the final replacement.
"Regardless of the situation in the pool, this is a local derby and there are certain bragging rights that go with them," Ryan said. "It would be great for our development and momentum to win this game and that is what we will be aiming to do."
GLOUCESTER (v Bath, 5.30pm): Olly Morgan; Karl Pryce, Mike Tindall, Jack Adams, Mark Foster; Willie Walker, Haydn Thomas; Patrice Collazo, Rob Elloway, Carlos Nieto, Jonathan Pendlebury, Will James, Jake Boer, James Merriman, Adam Balding. Reps: Jack Forster, Ross McMillan, Alex Brown, Rory Lawson, James Simpson-Daniel, Brad Davies. One to be confirmed.
There are still tickets available for tomorrow's game from the ticket office, the hotline number on 0871 871 8781 (option 2) or online at www.gloucesterrugby.co.uk