Wales flanker Dan Lydiate can return at the Pro14 on Saturday at home against Scarlets from injury for Ospreys.
Lydiate suffered a knee injury on Wales duty and last .
“Dan had a great start to the summer season and played a great game for Wales therefore it is great to have him back in contention,” said assistant trainer Matt Sherratt.
Wales first-choice prop Nicky Smith (ankle injury) is still outside.
But Ospreys are likely to remember current Wales players including Alun Wyn Jones, Owen Watkin, Aled Davies, George North, Adam Beard and Justin Tipuric, that sat their European Challenge Cup defeat at Stade Francais Paris last weekend.
Tonga prop Ma’afu Fia, fly-half Sam Davies and centre Scott Williams were rested.
“They’re usually tight affairs in the derbies, so having as much experience as you are able to get in the pitch is really of use,” said Sherratt.
Scarlets have won the previous four experiences contrary to their neighbours, including a 20-17 victory in October 2018.
Both teams got six wins while the Scarlets are winless at the top-tier European Champions Cup, although Ospreys have also won just two from four.
Captain Tipuric said:”It’s a huge game for every one if you’re an Osprey or perhaps a bright red. With the derby matches that you realize Christmas is around the corner and you have an excellent xmas or maybe not (based on the result).
“You are playing against (Wales) team-mates from yesterday now they’re the opposition.”
The ranks are likely to provide a number of their rivalry, with Ospreys’ former Scarlet Scott Williams, Watkin and Cory Allen matched against Hadleigh Parkes and Wales first-choices Jonathan Davies, along with Samoa’s Kieron Fonotia, a former Osprey.
“This game and both (derbies) once it will play a huge role in where we end up and everyone else would like to play at the three derby matches with lots of bragging rights at stake also,” said Watkin.
“It’s a fantastic test for us for the Six Nations if selected, with international rivalry at stake also.
“On an individual level I want to play than Hadleigh Parkes, because he’s able for Wales as well, but you can’t get too selfish.”