Complex sentence: This broke the previous record on YouTube for the highest number of views on a K-pop group music video within 24 hours, previously held by the music video of their own song "Blood, Sweat, and Tears".
Split into simpler sentences: This broke the previous record on YouTube for the highest number of views on a K-pop group music video within 24 hours. This record was previously held by the music video of their own song "Blood, Sweat, and Tears".