Ospreys pair Eli Walker and Nicky Smith, Cardiff Blues back Rhys Patchell, Scarlets flanker James Davies and Dragons back Hallam Amos have all been tipped to win a World Cup spot.
Wales coach Warren Gatland has said regional form will play a part when he selects his squad for the World Cup.
The five impressed during Saturday's 'Judgement Day' Pro12 Welsh derbies.
"I think Eli Walker has just got something, he's a natural finisher," said Wales great Jonathan Davies.
"He's had a dreadful run of injuries but he is international class.
"Hallam Amos again did some brilliant things again, so there's another come good.
"Our back three aren't strong so if one of them is injured then you've got to bring them in."
Walker has long been tipped for a Wales cap but each time the 23-year-old wing has come close injury has intervened.
Centre or wing Amos, 20, has won one cap, against Tonga in 2013, but was part of Wales' 2015 Six Nations squad and is expected to win many more.
Former Wales dual-code international Davies highlighted the two backs on BBC Wales' Scrum V programme, with his fellow guests Martyn Williams and Adam Jones choosing the outsiders they believe can make Gatland's World Cup squad.
"I think Nicky Smith was good. Obviously you've got Paul James and Gethin Jenkins who are your first choice [loose-heads], but I think they'll take him for the experience," said Jones - who won 95 Wales caps and five for the British and Irish Lions - of his fellow prop.
"He'll be with [Scarlets tight-head] Samson Lee [in the Wales front row] for the next 10 years."
Smith, 21, won his two Wales caps in the 2014 autumn Test series but tore a pectoral muscle in the loss to New Zealand that sidelined him until March.
Williams, the former Wales flanker who represented his country 100 times and won four Lions caps, picked out fellow open-side James Davies and Blues utility back Patchell.
"We've got so many good open-sides but I'm a massive fan of James Davies," said Williams.
"He was sensational again... the effort from him even when the game was won was incredible.
"Rhys Patchell is another one for me because he can cover so many positions.
"He's still got a lot to learn, he can develop a lot, but ball in hand he is dangerous."