Sage Northcutt Says He's Getting Better After Surgery For Face Fractures

Sage Northcutt is on the mend ... and he's giving a positive update on his health after undergoing surgery on facial fractures he suffered when he got his ass knocked out in his ONE Championship debut.

The ex-UFC posted this picture from his hospital bed in Singapore on Wednesday night ... thanking all his fans for their prayers and letting everyone know he's recovering and getting better, day by day.

Sage looks to be in good spirits, given the circumstances ... he's giving two big thumbs up, and doing his best to smile -- which has gotta be difficult when you have surgery to fix 8 FRACTURES!!!

Check out that shiner under Sage's left eye ... that's gonna last a while.

As you know ... Sage's debut was a disaster. The 23-year-old got his face punched out by Cosmo Alexandre, crumbling to the canvas with a thunderous face plant 29 seconds into the match.

Sage went under the knife over the weekend ... and his coach, Urijah Faber, told us the fighter's injuries were way worse than originally thought because Sage also shattered his cheek into 30 different pieces.