Khawaja and Labuschagne are both set to feature for the undefeated Brisbane Heat against Perth Scorchers at the Gabba on Wednesday while Carey will line up for Adelaide Strikers against Hobart Hurricanes the day before.
Their remaining two games are against defending champions Scorchers with those fixtures likely to determine who will finish top and host the Qualifier final on January 19.
“It will be good for the group to have Usman and Marnus back around the team, especially as we get into the business end of the competition,” Heat coach Wade Seccombe said.
Carey’s return is a boost for the struggling Strikers who are currently sixth with just two wins and will likely need to win their remaining three games to stand a chance of progressing.
A Strikers statement added: “In consultation with Cricket Australia medical staff, Travis Head will not be available for Big Bash selection during the break between international Test series”
It has yet to be confirmed whether Carey will be available for the return fixture against Hurricanes in Hobart on Thursday. Mitchell Marsh won’t be available for Scorchers against Heat in Brisbane on Wednesday.
Pat Cummins and Mitchell Starc signed as marquee supplementary players with Thunder and Sixers respectively this season so they can have a role promoting the competition but have never been in line to play. Cameron Green does not have a BBL deal having opted not to take one this season due to a combination of the schedule and to focus on red-ball cricket.
Lance Morris (Scorchers) and Scott Boland (Stars) have previously been released from the Test squad to play in the BBL.
Nathan Lyon won’t be able to debut for Melbourne Renegades this season with their next game on Saturday, the day the Test squad is due to gather in Adelaide ahead of the first Test against West Indies from January 17.
There is set to be a far larger window for Australia’s Test players to feature in the BBL next season with the Sydney Test against India in the first week of January to be the last of the home summer. This season’s schedule was pushed to a later start due to the ODI World Cup.