Australia captain Mitchell Marsh will be restricted to batting in the team's T20 World Cup opener against Oman, head coach Andrew McDonald said, with the allrounder easing back into action after a long layoff due to a hamstring issue.

Batting at No. 3 three, Marsh was dismissed for four runs as a depleted Australia lost its final warmup against co-host West Indies by 35 runs in Trinidad and Tobago on Thursday.

McDonald said Marsh was tracking well in his recovery but still not ready to bowl.

"It won't be first game," he said.

"He fielded more overs again tonight, he was able to move more freely, so he's building a little bit of confidence there."

Marsh was run out for 18 opening the batting in Australia's first warmup, a seven-wicket win over Namibia.

As with the Namibia game, Australia had only nine players available from its World Cup squad against the West Indies, and used McDonald as one of the substitute fielders.

The West Indies' batters smashed 257 for four before restricting Australia to 222 for seven.

Wicketkeeper-batsman Nicholas Pooran roughed up Australia's spinners Adam Zampa and Ashton Agar with a 25-ball 75, while Rovman Powell scored 52.

"To concede 260-odd runs in a T20 game is not ideal, but we were working through some plans, working through what we needed to get out of the game," McDonald said.

Australia, the test and 50-overs world champions, play Oman in Barbados on June 5.