Halfpenny has recovered from a concussion suffered on international duty with Wales during the autumn series and has been released from the national camp to play this weekend.
He is joined in the match-day 23 by fellow Wales squad members Wyn Jones, Ryan Elias, Jake Ball and Rhys Patchell as head coach Wayne Pivac makes four personnel changes to the side that was beaten 25-19 by Benetton last weekend.
Halfpenny’s return at full-back sees Johnny McNicholl switch to the wing in place of Steff Evans in the only change behind the scrum. Evans remains in the Welsh camp.
The back row is the same as the one that took the field at the Stadio Monigo with South African No. 8 Uzair Cassiem going up against his former side.
On the bench, Javan Sebastian comes in to provide tight-head cover, Tom Phillips has recovered from a hamstring injury, while Sam Hidalgo-Clyne replaces Jonathan Evans, who is set to miss the rest of the season because of an ankle injury.
The Scarlets sit fifth in the Conference B standings.
“It’s a must-win game for us. I am expecting a response this weekend. It is a home game and we have a proud record at home and we want that to continue,” Scarlets head coach Wayne Pivac said.
“I am pretty sure the boys will be up for the game and fully motivated because a lot of them are disappointed with individual performances from last weekend.
“If you look at our run-in, it isn’t too bad when you compare to other teams. Of course, we still have difficult opponents to play, but we are in Wales which is in our favour. Everyone likes playing at home and we have four out of our last six games at home and one at a neutral venue.
“The Cheetahs kick the ball the least so they like to play, they have some genuine speed, they score a lot of points and they concede a lot of points.
“For us, it is about being disciplined; our defensive effort has to be better than it was against Benetton and we have to make sure we win those physical exchanges when we have ball in hand so we can unleash our backs who we believe are pretty potent.”
Scarlets Team v Cheetahs:
Leigh Halfpenny; Johnny McNicholl, Kieron Fonotia, Paul Asquith, Ioan Nicholas; Dan Jones, Kieran Hardy; Wyn Jones, Ryan Elias, Werner Kruger, Jake Ball (capt), Josh Helps, Josh Macleod, Dan Davis, Uzair Cassiem.
Replacements: Marc Jones, Phil Price, Javan Sebastian, Lewis Rawlins, Tom Phillips, Sam Hidalgo-Clyne, Rhys Patchell, Steff Hughes.
Players unavailable because of injury:
Jonathan Evans (ankle); James Davies (foot), Steve Cummins (shoulder), Blade Thomson (concussion), Angus O’Brien (knee), Aaron Shingler (knee), Taylor Davies (hamstring), Corey Baldwin (ankle), David Bulbring (ankle/knee).
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