The big-hitting Jake Fraser McGurk and Matthew Short are likely to be Australia's travelling reserves for the T20 World Cup which begins on June 1.
The 22-year-old McGurk has been in blazing form for Delhi Capitals in the IPL.
But the top-order batter, who is yet to make his T20I debut, missed out on the 15-member provisional squad because Australia already have an established top three in David Warner, Travis Head and captain Mitchell Marsh.
Batting all-rounder Short, on the other hand, played nine of Australia's last 14 T20Is, opening in five of them and he was also the Big Bash League player of the tournament in back-to-back seasons.
"Australia's chair of selectors George Bailey had suggested that Australia would carry just one reserve to the Caribbean when the provisional squad was announced, but they are likely to add a second with the in-form Fraser-McGurk set to be named alongside Short," ESPNCricinfo reported.
The Australian World Cup squad will fly to the Caribbean on Thursday for a training camp in Trinidad that will include two practice matches against Namibia and West Indies on May 28 and 30 respectively.
Head, Cameron Green, Pat Cummins, Mitchell Starc and Glenn Maxwell, who are all locked to play in the IPL playoffs, will join the squad later.
Players like Marsh, Warner, Agar, Josh Hazlewood, Adam Zampa, Matthew Wade, Nathan Ellis and Josh Inglis have played little cricket since the end of the Australian domestic summer in March.
Under ICC rules, only players named in the 15-man squad can compete in the warm-up fixtures.
"Marsh, Hazlewood, Inglis, Zampa and Agar have all trained in Brisbane over the past fortnight along with Short. Marsh is understood to have recovered from his hamstring injury but he is still yet to bowl," the report added.
Australia began their campaign against Oman in Barbados on June 5.
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