Ashton Agar's turbulent 2018 has continued after the left-arm spinner was rested from Western Australia's team for their JLT Sheffield Shield match against Victoria by request.

Originally included in the Warriors' 14-man squad for their final Shield game before the KFC Big Bash break, Agar was omitted from the final XI on Friday morning.

Western Australia coach Adam Voges confirmed he's been rested following a wildly-fluctuating few months in regards to the amount of cricket he has played.

Agar is expected to spend the coming days in his hometown Melbourne where his family, including brothers Wes (a Victorian squad member) and Will, still reside.

QUICK SINGLE Agar brothers take backyard to big stage

After an action-packed winter, the 25-year-old has played just four games since the start of the Australian cricket season – one JLT One-Day Cup game for WA in September, two T20Is in the UAE in October and a Shield game against NSW last week.

While he's sent down countless overs in the nets, he's bowled just 30 overs in the middle.

"It's been a long year of cricket for Ashton," said Voges. "He was playing in the UK, then he was traveling internationally and domestically for the last few months with the Australia squad.

"It's been a long time on the road and he just needs this week to freshen up and have some quality time at home."

Agar is expected to be right for the start of the Scorchers' BBL campaign, with last season's semi-finalists to begin their campaign in Melbourne against the Renegades on December 20.

His lack of game-time for the start of the 2018-19 summer stands in stark contrast to his hectic winter, which saw him play 24 matches in three months.

A rare bright spot during Australia's 0-5 one-day international series whitewash to England in June, Agar then travelled to Zimbabwe for a T20 tri-series.

After heading back to the UK for Middlesex's county T20 campaign, he then went to India for the best part of a month for 50-over and first-class matches with Australia A.

But his subsequent selection in Australia squads to play in Tests and T20Is against Pakistan in the UAE, in ODIs and a one-off T20 against South Africa and then in three T20s against India put an abrupt halt on the constant action.

Best of BBL|07: Amazing Ashton Agar

Agar stayed back in Australia for WA's opening JLT Cup game before running drinks for two Tests in Dubai and Abu Dhabi as Nathan Lyon and Jon Holland performed spin duties. He then bowled a combined five overs in T20s against the UAE national side and Pakistan before being dropped as Adam Zampa was preferred as the sole spinner.

On his return home, Agar missed selection for all three ODIs against South Africa, the one-off T20 against the Proteas and then three more T20s against India, meaning he went a month without playing a match.

He finally returned for WA's Shield clash with NSW last week where he bowled 15 overs in a 104-run defeat.

Western Australia went into Friday's Shield match without a specialist spinner, with Victoria reaching 2-79 at lunch on day one.