NOT FOCUSED ON THE GAME TMZSports.com
Warren Moon believes Deshaun Watson's legal woes are contributing to his recent stretch of poor play ... telling TMZ Sports, "I think a lot of his problems are mental."
The Cleveland Browns star, of course, has battled double-digit cases in courtrooms throughout the past few years ... and, just recently, he was sued once more by another woman accusing him of sexual assault.
The quarterback hasn't ever said publicly if it's all affected him on the field .