They’re the youngest and oldest men to be chosen in a Wallabies’ World Cup squad, and veteran Adam Ashley-Cooper and uncapped Jordan Petaia shared the same pre-selection nerves after taking very different paths to Japan.

After 118 caps, 35-year-old-utility back Ashley-Cooper becomes the second Wallaby after George Gregan to be selected for four World Cups.

Victoria-born Queenslander Petaia, 19, suffered a serious foot injury in early March and has won selection on the back of recent club rugby performances.

While Ashley-Cooper had banked plenty of credits during an international career stretching back to 2005, his only Test appearance so far in 2019 was a brief cameo in last week’s Bledisoe Cup loss to New Zealand.

“Selection is never guaranteed, but this one here was really nervous around whether or not they felt I could still perform and add value and contribute,” Ashley-Cooper told AAP after the squad was unveiled in Sydney on Friday.

“I’ve been away (overseas) for a few years and I’d only played a handful of minutes in the lead up to this selection so I was relying on my performances at training and the way i was contributing as a senior player to get me through and thankfully it did.”

Ashley-Cooper decided 18 months ago to aim for a fourth World Cup appearance ,as he was preparing for a second season in Japanese club rugby.

“I actually hadn’t done that as a rugby player before … create such a long term goal, work on it every day and think about it every day,” he admitted.

Like Ashley-Cooper, Petaia was informed of his selection over the phone by Wallabies centurion Matt Giteau.

“I wasn’t sure what was going to happen, I was really nervous,” Petaia said.

The teenager initially dreamt of being a professional footballer but switched focus to rugby in his final year of high school.

Petaia enjoyed a fine rookie season in Super Rugby for the Reds before injury denied him a Test cap against Italy on last year’s spring tour.

“I had to work a lot harder with the rehab, stay strong, not give in and keep working just to hopefully get here,” Petaia said.

“As I progressed I started to see the light at the end of the tunnel.”