The Italian tennis player Nardi clinched the biggest win of his career after beating the world number one by 6-4, 3-6, 6-3.
The 20-year-old rookie started well against Djokovic and clinched a 6-4 win in the first well. However, in the second set, the 36-year-old displayed his experience and made a comeback with a 3-6 win.
But the Serbian failed to maintain consistency in the third and final set as Nardi beat Djokovic by 6-3.
After sealing a historic win against Djokovic, Nardi said that he was "super happy" with the victory in the third round.
"I think that before this night no one knew me. I hope that the crowd enjoyed the game. I'm super happy with this one," Nardi was quoted by ATP as saying.
The Italian also called his win over the Serbian a "miracle".
"I don't know [how I held my nerve]. I think it is a miracle because I am a 20-year-old guy, 100 in the world, and beating Novak. It's crazy," he added.
Earlier in the previous round, Djokovic survived an opening-round scare against world no 69 Australian Aleksandar Vukic to eventually grind out a 6-2, 5-7, 6-3 victory on Sunday.
Djokovic has been a five-time Indian Wells champion and was participating in the ATP Masters 1000 for the first time since 2019.
The Serbian was chasing a record-extending 41st ATP Masters 1000 championship in California, but his shocking defeat to Nardi bared him from winning a record sixth Indian Wells.
