New Zealand international Steven Luatua will skipper the side for the round one West Country derby clash.
Charles Piutau (shoulder) misses out, while another new arrival – Aly Muldowney (neck) – is also unavailable for selection.
Lam said: “It brings huge responsibility. We have to go out there and celebrate the work that we do on the training ground and put our teamwork into practice. Everybody is busting a gut to be involved at Ashton Gate.”
Bristol Bears team to face Bath Rugby at Ashton Gate on Friday, August 31st (7.45pm KO):
15. Luke Daniels 14. Luke Morahan 13. Will Hurrell 12. Tusi Pisi 11. Alapati Leiua 10. Ian Madigan 9. Nic Stirzaker 1. Yann Thomas 2. Harry Thacker 3. John Afoa 4. Ed Holmes 5. Chris Vui 6. Steve Luatua (c) 7. George Smith 8. Jordan Crane