With Ceiron Thomas moving to the bench, Darren Daniel slips out of the match 22.
"We know Ulster will be a stiff challenge," admitted Davies. "They are a quality side and have a core of players who bring experience in key areas. They had a fantastic result last week when they beat Toulouse, so it should be a cracking game at Stradey Park on Friday."
"The big thing about Friday is that we know what to expect," said Scarlets coach Paul Moriarty.
"Toulouse were not prepared for what Ulster threw at them.
"For us the away win at London Irish was vital, with the bonus point a massive plus.
"Our finishing and our set pieces were very good, the scrum was very efficient.
"But we have had some great games with Ulster over the last four seasons, we seem to thrive off each other and give each other a lot of respect."
The Scarlets' Scotland second row Scott Macleod remains out with a leg injury, while Dafydd Jones is a long-term casualty.