Van de Zandschulp was up a set and 3-0 on Nick Kyrgios in his first-round match on Stadium One on Thursday before the Australian withdrew with wrist pain.

Djokovic, 37, retired from his Australian Open semi-final against Alexander Zverev with a hamstring injury and lost in the Qatar Open first round last month.

He said the leg injury was behind him coming into the tournament and did not look hampered by it in his match on Saturday, where he was accompanied by coach Andy Murray.

"No excuses for a poor performance," Djokovic said.

"It doesn't feel great when you play this way on the court, but congratulations to my opponent.

"Just a bad day in the office."

Djokovic's loss led a day of upsets that included seventh seed Andrey Rublev losing 6-4 7-5 to Italy's Matteo Arnaldi and 17th seed Felix Auger Aliassime falling to American Jenson Brooksby 6-4 6-2.

World number one Jannik Sinner is not playing at the tournament as he serves a doping suspension.

Keys And Alcaraz Cruise

Earlier, Australian Open champion Madison Keys crushed Anastasia Potapova 6-3 6-0 in her first match as a Grand Slam champion, while Carlos Alcaraz began his bid for an Indian Wells three-peat with a 6-4 6-2 win over Quentin Halys.

Alcaraz is looking to join tennis greats Novak Djokovic and Roger Federer as the only players to have triumphed three successive times in "Tennis Paradise".

"I couldn't wait to start the tournament, to get here again," the Spaniard said after dispatching his French opponent.

"Outside my country, this is my favourite tournament by far. It's a privilege."

Alcaraz will play Canadian Denis Shapovalov in the third round.

Twelve months ago, a swarm of bees on Stadium One court stung Alcaraz and suspended play for nearly two hours during his quarter-final.

Lance Davis of Killer Bee Live Removal played the hero that day, removing the bees from a moving camera over the court without harming them, and Alcaraz and Davis met at the net before Saturday's match where they shook hands and shared a laugh.

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