JAPANESE qualifier Taro Daniel sent five-time tournament champion Novak Djokovic tumbling out of the Indian Wells Masters with a hard-fought 7-6 (7-3) 4-6 6-1 victory on Monday (AEST).
It was another snag in the return for the 30-year-old Djokovic who was playing in just his second event of 2018 after the Australian Open in January.
He is making a cautious return to the ATP Tour after stopping his 2017 season following Wimbledon, due to a right elbow injury.
Djokovic scrambled to win the second set but looked rusty on stadium court, making 62 unforced errors compared to 29 for Daniel.
Djokovic had four aces but overall he served poorly making four double faults and winning just 65 per cent of his first-serve points.
Daniel, who is ranked 109th in the world, advanced to the third round where he will face Gael Monfils of France who outlasted American John Isner 6-7 (5-7) 7-6 (7-3) 7-5.
Speaking after his upset win, Daniel said the Djokovic he bounded out of the tournament was not the one the tennis world is used to admiring.
"The Djokovic I know is like the Djokovic I have seen on TV, and he never misses a ball. He puts the ball wherever he wants," Daniel said. "Today, obviously he was missing a lot of balls but, I mean, even then you still have to beat him."
Djokovic said he felt like it was his "first match" on tour and was unable to explain his opening set stumble or his capitulation in the decider.
"Very weird - I just completely lost rhythm," Djokovic said. "Yeah, everything, nerves were there.
"I made so many unforced errors that it was just one of those days where you are not able to find the rhythm from the baseline especially from the backhand side. That has always been a rock solid shot for me throughout my career.
"Just some inexplicable, uncharacteristic errors, but that's I guess all part of those particular circumstances that I'm in at the moment."
New York Times tennis writer Christopher Clarey said the Serbian's "crisis continues" as he searches for his first grand slam title since the French Open in 2016.
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