Here he is ... the KC Chiefs trainer who helped save a closeted gay NFL player from killing himself, David Price, tells TMZ Sports he was "elated" to find out he had such a positive impact.
The player is ex-offensive lineman Ryan O'Callaghan -- who recently came out publicly on Outsports.com after keeping his sexuality a secret during his entire football career.
O'Callaghan -- who played for the Patriots and the Chiefs -- says he was in a dark place toward the end of his career and was on the verge of suicide .