Johnny Manziel Says Lamar Jackson Will Win Heisman, BUT DON'T GO TO CLEVELAND!

Johnny Manziel is convinced Lamar Jackson will win the Heisman Trophy on Saturday -- but when we asked if he should take his career to Cleveland ... Johnny turned into Dikembe Mutombo!

The ex-NFL quarterback is back in L.A. after celebrating his 24th bday in Miami this week -- and hit up Catch (the hottest restaurant in town) with a few friends.

We talked about Cam Newton and Lamar ... but when the topic turned to Cleveland, it's clear Manziel wants Lamar to steer clear of the Browns.

The last time we talked Cleveland with Manziel, seemed he was on better terms ... saying he wishes them all the best but knows he'll never play there again.