Ariana Grande's Manager Scooter Braun's Emotional at One Love Manchester

Ariana Grande's manager Scooter Braun did the honors by introducing the crowd at One Love Manchester to his artist ... and he got emotional.

Scooter talked about a conversation he had with Ariana a week ago, when she told him she couldn't live with herself after the terrorist attack at her concert 2 weeks ago unless she did something.

Not what we expected ... we thought Ariana would go last. But whether they're going out of order or not ... no one seems to mind.