Gary Gray has become the third federal West Australian Labor MP to quit politics in the past month, saying he believes the party will lose the next election.
The 57-year-old, who has held the seat of Brand since 2007 and was resources minister and special minister of state in the Rudd government, said he felt it was time to move on and "support renewal" in the state's federal representation.
"I think we'll lose, but it's not about being able to bear the strain of that," Mr Gray told ABC radio.
Opposition Leader Bill Shorten brushed off Mr Gray's comment, saying the party had always been the underdogs and historically started very few elections as favourites.
He said refreshing the team with young blood was a good thing.
"He did also rather generously say that if anyone could, he thought I could," Mr Shorten told reporters in Perth.
"He's making the point - and of course I've spoken with him - is that it is a hard battle for a first term opposition.
"He understands that this is a big fight, and he understands that Labor needs the opportunity to present candidates that are going to be going around this time and next time and the next time."
Fellow West Australian MPs Alannah MacTiernan and Melissa Parke also recently announced they would not recontest their respective seats of Perth and Fremantle at this year's election.
Ms MacTiernan cited impatience with the progress of her political career in Canberra, while Ms Parke said she wanted to be closer to her family and travel less.
At the same time, Ms MacTiernan said it made sense to "pass on the baton to someone who can build a bigger role over the next decade" while Ms Parke said renewal was "a good tonic" for the party.
That sentiment was echoed by Mr Gray, who said he was in favour of "regeneration and renewal" and more diversity in parliament, describing himself as an "old, white guy".
Mr Shorten said he respected their choices.
"The toll for Western Australian federal MPs, to be able to represent their state in the nation's capital is a very demanding one," he said.
He talked up Labor's young candidates, specifically Matt Keogh, Anne Aly and Tammy Solonec, saying they would "become household names in the future".
"This is a good chance to rejuvenate our offerings to the people of Western Australia.
"You'll see more talented people emerge to take up the challenge."
While Mr Shorten acknowledged it would be a hard election for Labor, he expected to not just retain three WA seats, but add to them.
WA Opposition Leader Mark McGowan said he believed the three closely-timed announcements were coincidences.
