Fly-half Sam Davies is released with Rhodri Jones, Rory Thornton, Olly Cracknell. Nicky Smith and James King.
They will return to the Wales camp on Sunday to prepare for the Six Nations game with Ireland on 10 March.
The other Welsh regions play on Saturday and will not receive players from Rob Howley's squad, with Wales playing just six days later.

A 36-year-old man has been charged with causing a dangerous article to be on a road.
Another man, 46, has been charged with riotous behaviour.  Both are due to appear before Belfast Magistrates Court 28 July.
A crossbow was among items seized after the PSNI dispersed what they described as "a large crowd of men".
A police spokesperson said: "Reports suggested some of the males were masked and may have been armed with weapons such as hammers.
"Officers attended and dispersed the crowd seizing a number of items including a crossbow."
Pictures from the Castlemara estate show a burning bonfire and police officers removing tyres and pallets from the road.
At least one fire appliance was in attendance.
The DUP MLA for the area, Gordon Lyons, said: "People in Carrickfergus are very disappointed at the disturbances that look place last night.
"It's not what we want to see in 2016."

Kent Police are set to prioritise fresh produce hit by problems in Calais, following weeks of disruption by migrant activity and French strikes.
Scottish ministers said it would help protect Scotland's seafood exporters.
They have been looking at ways to help Scottish firms hit by the ongoing migrant crisis in France.
Earlier this week, it said the seafood industry was in need of urgent help, following talks with Scottish exporters.
The Scottish government said the move by Kent Police followed representations by ministers.
Scottish Food Secretary Richard Lochhead said: "The Scottish government has repeatedly called for action from the outset of this disruption, and so I welcome this move to prioritise key consignments - including fresh produce - through the Channel Tunnel and Port of Dover.
"At last we are seeing common sense prevail and a recognition of the impact on food exporters.
"Agreement of this protocol to prioritise a quick-to-market route is real progress and we will, of course, monitor its introduction and effectiveness."
He added: "While it is by no means a solution to the wider and on-going complex situation in Calais, it will be welcomed by Scottish seafood exporters who have seen orders plummet by up to 80% in some categories in recent weeks."
"With seafood exports worth five times as much in Scotland as the UK as a whole, we have been determined to find a way forward.
"With no end in sight to the situation at Calais, we will continue to look at options around alternative routes which could be used by hauliers."

The ATM at the Cooperative store on Argyll Road was robbed at 03:00 on Tuesday. Police said the gang made off with a "quantity of cash".
Officers are carrying out door-to-door inquiries and reviewing CCTV of the raid.
Police Scotland asked anyone who noticed suspicious activity near the store to contact them.
Ospreys will be boosted by six Wales squad members for their Pro12 match with Edinburgh on Friday, 3 March.
[NEXT_CONCEPT]
Two men have been charged following disturbances in Carrickfergus, County Antrim, on Friday night.
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The Scottish government has welcomed plans to pilot a "quick-to-market" route for vehicles hit by delays at the Channel Tunnel.
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Thieves have stolen money from a cash machine in Perth after smashing their way into a supermarket.