Scott set for 2018 debut at Pebble Beach

Adam Scott has warned critics to write him off at their own peril in 2018, especially on golf's major championship stage.

Commencing his 19th year on the US PGA Tour at this week's Pebble Beach Pro Am, Scott aims to end to a five-year drought at the majors since he became the first Australian to win the Masters, in 2013.

First, the 37-year-old will need a string of hot results - at Pebble Beach, the LA Open at Riviera Country Club and the Honda Classic in Florida in successive weeks - to even secure a place in all four majors this year.

Dropping to a world ranking of No.43 after a winless 2017, Scott's starts at the US Open and PGA Championship are under threat.

But the Queenslander believes the birth of his second child last year has allowed him to enter a new chapter in his career.

"I want to achieve a few things by the time I turn 40. If you said three more major championships in four years; one a year is achievable," Scott said.

"I don't think it's (all) going to happen in one year, but it's too much to ask; it's winning a tournament.

"Of course, it's tough to do but Jordan Spieth has (won three majors) in the last three years and I don't see why I couldn't aim for something similar.

"But to do that, there's a process of getting my game, confidence and belief to a certain point for April."

Almost two years since his last victory, the former world No.1 has seen a brigade of younger peers take hold of the rankings.

But Scott isn't worried about the seven golfers in their 20s who currently crowd the top 10.

"I don't think any of the older players are really fearing the young guys," he said.

"As much bravado as (they) have and the performances they've been putting in, which are great, there's still nothing they're doing I don't see older guys able to do.

"What's very hard now is to play at the top level week in, week out."

An injury-free Scott is confident of playing great golf well into his 40s.

"Essentially, I have zero injuries or restrictions or niggles. My body is holding up great and nothing is holding me back," he said.

Playing the Pebble Beach Pro Am for just the second time, Scott recently revealed he is unlikely to play the tournament prior to each major this year.

He did that in 2017 while he and wife Marie awaited the birth of their son, Byron.