Rachael Ostovich Cleared to Fight Paige VanZant, 'Fight Back On!'

Great news for Rachael Ostovich -- the fighter has been cleared to get back in the Octagon after her domestic violence incident ... and now her fight with Paige VanZant is BACK ON!

TMZ Sports broke the story ... Ostovich was hospitalized with a broken orbital bone and other injuries after a violent Nov. 18 incident with her husband, Arnold Berdon, who is also an MMA fighter.

Berdon was arrested and charged with felony assault -- he's pled not guilty. Family members have told us he will argue he was defending himself. Ostovich has obtained a restraining order against him.

Initially, it seemed Ostovich's injuries were so severe, she wouldn't be able to fight again in January -- but she got a second opinion which gave her the go-ahead to take the bout.

Now, Ostovich's manager, Brian Butler-Au, says Rachael has been cleared to fight again and WILL compete against VanZant on January 19 in Brooklyn.

As for Paige, she's fired up about the news -- tweeting, "FIGHT STILL ON!!!!! I couldn’t be more great full to @rachaelostovich."