Premier Daniel Andrews is facing a new political firefront, this time over the question of which MP to promote to cabinet to fill the vacancy left by Jane Garrett.

The ex-minister, who quit over the controversial deal with the firefighters' union, has left a power vacuum on the front bench.

Cabinet secretary Marle Kairouz alongside Premier Daniel Andrews and Deputy James Merlino at Labor's first Cabinet meeting in 2014. Many have tipped her to be replace Jane Garrett in Cabinet. Credit:Justin McManus

Tensions in the caucus are still burning over the fallout from last week's showdown with Ms Garrett and the CFA, but attention has turned to her replacement - with the right and left factions fighting to claim the job.