“With Bristol we know what we’re getting – it’s probably a supercharged version of the way we attack,” Gloucester director of rugby George Skivington told BBC Radio Gloucestershire.
“We know it’s going to be fast, we know it’s going to be a lot of actual minutes of running round.
“I think our attack is closer to Bristol and they do a lot of good stuff at set-pieces as well. I don’t think our identity is a million miles away.
“They are very wide-to-wide and they have some great one-off moments and Pat’s very sharp with the areas he targets in games.”
Gloucester finished ninth last season and were the second-lowest scorers in the league, ahead of only Newcastle.
However, the signings of Wales scrum-half Tomos Williams and fly-half Gareth Anscombe last summer have helped revolutionise their backline.
When the two sides met in September’s reverse fixture in round two at Ashton Gate, Gloucester edged an 85-point thriller 44-41.
Lam said they were “shocked” by the Cherry and Whites that day.
“It’s fair to say they shocked us in round two – we didn’t expect they’d come out playing that way, and having Tomos Williams and Gareth Anscombe and Santi Carreras they certainly played to their strengths,” Lam said.