Former Wales flanker Martyn Williams says clubs must decide when to rest their British and Irish Lions stars.
The Scarlets, Dragons and Cardiff Blues chose to overlook their Lions in the opening round of the Pro12 after a gruelling tour of Australia.
Adam Jones, Richard Hibbard and Ian Evans came off the bench for Ospreys' win at Treviso, but Alun Wyn Jones and Justin Tipuric were rested.
"It's a difficult balancing act for everyone," ex-Lions star Williams said.
"If your region loses one or two then you're thrown in there.
"Some boys are better when they play week in week out and some boys are better when they've had a longer rest."
Former Ospreys coach Sean Holley, a fellow panellist on Scrum V with Williams and Jonathan Davies, warned that 32-year-old prop Jones needed to have his game time managed carefully.
"I think someone like Adam Jones is going to be hugely required [later in the season]... we don't want to flog someone like Adam in Wales because we need him for the big moments," Holley said.
The Welsh Lions who have joined clubs in England and France have mostly gone back into club action earlier than their counterparts still with the four Welsh regions.
George North made his competitive debut for Northampton against Exeter in the Aviva Premiership at the weekend, while Dan Lydiate and Jamie Roberts - at French side racing Metro - are already several weeks into the new season.
"At the moment the Wales team has been very successful and we're all absolutely delighted, but the bread and butter stuff for the French and English is their league, and they play a lot in the league," added Davies.
Dragons coach Lyn Jones said he had no hesitation in leaving Toby Faletau out of the win over Ulster on Friday.
"For Toby I'm sure he'll have some involvement, if not next week, then certainly against the Scarlets," Jones said.
"It's going to be difficult for Wales in the Six Nations and Dan [Lydiate].
"I think Mike Phillips proved in 2009 when he played the first game for the Ospreys away to Connacht and Mike's game fell off December time.
"We need to look after our players and the Irish Union are very good at looking after their players.
"There's a balance to do well at the Rabo [Pro12] and for Wales to do well.
"That was the whole idea of starting regional rugby, to get the balance, to improve our European performances and to make Wales a successful nation.
"That's why regional rugby is a massive success."