Chad Ochocinco is up to his old tricks ... trying to mess with his next opponents -- the Atlanta Falcons -- by sending their defensive backs t-shirts with his mug plastered all over the front.
Sources close to Chad tell us the Cincinnati Bengals star shipped boxes of shirts featuring the "Mad Chad" character from his iPhone app to Falcons cornerbacks Brent Grimes, Dunta Robinson and Chris Owens and safeties William Moore and Thomas DeCoud.
If you recall, Chad sent gift baskets of deodorant to the Baltimore Ravens last year ... so they didn't sweat the matchup. And in 2004, he sent Pepto-Bismol to the Cleveland Browns -- insisting they would be sick to their stomachs trying to cover him.
So why the t-shirts this year? We couldn't get an explanation from Chad ... but we're guessing he'll probably have some sort of explanation before Sunday's game.