He went for leg at first but the brief turtle b4 pulling guard likely helped persuade ref to call it. Hindsight maybe tad early but he dropped awkwardly and looked dazed. Turtle is more acceptable if being rode from behind can setup a sit out or roll out but opponent in front punching down. Such a call during title fight would be boo’d but at that level both know to intelligently defend better. this fight less consequential so slides By.