Dwayne 'The Rock' Johnson -- He Wasn't Cooking a Thing at 'Da U' ... Says Ex-SNL Star Finesse Mitchell

Dwayne Johnson would be nearly unrecognizable, if you met him back in his college days -- because he was more like 'The Wallflower' than "The Rock" ... according to his old teammate Finesse Mitchell.

The SNL alum -- who, yes, played football at Da U with Dwayne -- says DJ was overshadowed by much bigger personalities ... like Warren Sapp. We got Finesse at The Grove in L.A., and he said both guys were beasts on the field ... but when it comes being the life of the party -- it was no contest.

In fact, the way Finesse describes it ... NO ONE could've predicted Dwayne would be the Hollywood superstar he is today.