While Jayson Tatum's right leg needed repair, his attitude clearly requires no adjustment ... check out a photo he just posted, he seems to be in good spirits despite undergoing brutal surgery.
Tatum's been hanging out in a hospital ever since he blew out his Achilles in Game 4 of the Celtics' playoff matchup with the Knicks, but in a pic he shared to his Instagram page Wednesday morning, he showed he's not letting it all keep him down.
Tatum -- whose right ankle was heavily bandaged -- had a smile in the snap .