Former Saracens fly-half Duncan McRae is predicting "the chance of a lifetime" for his new Western Australia team-mates against the Lions on Friday.

McRae, who criticised the London club he left last month for not hanging on to key players, is making a one-off appearance for WA on the bench before probably facing the Lions again for New South Wales later in the tour.

Wallabies coach Rod Macqueen is monitoring the 26-year-old's progress, as well as that of another Western Australia "ringer", prop Patricio Noriega.

The pair have temporarily joined a team of local amateurs whose professions range from carpenters to quantity surveyors.

Both McRae and Noriega will feature as second-half substitutes but the fly-half admitted his one-season Saracens sojourn was a frustrating experience.

An end-of-term exodus saw McRae, English international quartet Dan Luger, Danny Grewcock, Julian White and Tony Diprose, together with Ireland's Paul Wallace, all leave Saracens.

"I am surprised that so many top players have left Saracens. It is particularly disappointing and harsh on the fans,'' McRae said.

"The club has to take some blame. They should have got players signed up when they had a year left on their contracts, rather than wait and let things run on.

"Someone like Danny Grewcock is a world-class player that you can base your team around, but he has gone."

Grewcock, Luger and Saracens' England flanker Richard Hill will all be in the Lions line-up tomorrow, with McRae believing he can only benefit from such an experience.

"The more exposure I can get against world-class players, the better,'' he added.

"You look at the names in the Lions squad and it's outstanding really. There is going to be so much competition for places as the tour develops.

"We are under no illusions about Friday's game. We accept that it going to be an uphill battle for us, but there are a group of guys here who know that to play against the Lions is the chance of a lifetime."

McRae and Noriega apart, Western Australia coach Tom Fearn believes that "two or three" of his team could make the huge step up to Super 12 rugby, yet it will be a surprise if the Lions don't hit at least a points half-century.

"If we can keep them to 40 or 50 points, then I will be happy with that," said WA's Wales-born skipper Trefor Thomas.

"I think that our fitness levels will be okay for around 60 minutes, but we are hoping that our spirit will see us through and keep it respectable."

The Lions worked out at the WACA on Thursday morning, where local officials are confident of attracting a 15,000-plus crowd after advance ticket sales smashed previous records.

"I expect a lot from the WA team _ pride in the jersey and a lot of passion,'' said Lions captain Keith Wood, at the helm while Martin Johnson sits out what should be the tourists' easiest match.

Most pundits expect a points blitz, with rookie full-back Brian O'Driscoll spearheading the onslaught alongside English dangermen Luger, Ben Cohen and Will Greenwood.

O'Driscoll apart though, Lions coach Graham Henry probably won't learn too much from proceedings.

Next week's tougher tests in Queensland against a President's XV and Super 12 outfit the Reds should prove much more revealing.