Sage made a critical error due to lack of experience and ducked for a takedown when he should have straightened up knowing he has nothing for Gall on the ground. But before that costly mistake he clipped Gall a few times and might have got the finish later in the round. In short: Gall's striking got exposed badly. Other mistake by Sage, he was dancing around too much, taunting, when he was in no position to do so. Hopefully not low fight iq but just lack of experience.