Full race: The mixed 4x400m relay final starts at 8:34.00 mark in this full day event video:

Indian medallists at U20 Worlds

Edition ATHLETE EVENT MEDAL WON PERFORMANCE
2002 - Jamaica Seema Antil Discus Throw Women BRONZE 55.83m
2014 - USA Navjeet Kaur Dhillon Discus Throw Women Bronze 56.36m
2016 - Poland Neeraj Chopra Javelin Throw Men Gold 86.48m (U20 WR)
2018 - Finland Hima Das 400m Women Gold 51.46s
2021 - Nairobi Barath, Priya, Kapil and Summy Mixed 4x400m Bronze 3:20.60s
2021 - Nairobi Amit Khatri 10000 race walk men Silver 42:17.94s
2021 - Nairobi Shaili Singh Long jump women Silver 6.59m
2022 - Cali Barath, Priya, Kapil and Rupal Mixed 4x400m Silver 3:17.76s (Asian Record)