A 10th career Grand Slam semi-final for Sabalenka was starting to look unlikely at the start of the third set.
Sabalenka’s serve wavered and Pavlyuchenkova broke five times in a row to take the second set and go up a break in the third.
But despite having momentum on her side, the Russian 27th seed could not make the most of her early lead, and Sabalenka levelled immediately.
The three-time major winner settled herself with a hold to go 3-2 up, claimed a crucial break for a 5-3 lead before serving out a 19th successive victory at Melbourne Park.
Sabalenka, who has reached the semi-finals in eight of her past nine Grand Slam appearances, joked afterwards that she would make her team get tiger tattoos if she won the Melbourne title.
The 26-year-old said the tattoo of a tiger on her forearm is a “reminder of never giving up, staying aggressive, staying hungry and pushing myself no matter what is going on in life.”
She added: “If I win the Australian Open, which hopefully I do fingers crossed, we are going to celebrate.
“Then I’m going to call a tattoo specialist so they wake up with a tiger tattoo.”