Andy Murray was stunned in his opening match at the BNP Paribas Open by a man ranked 128 places below him, losing 6-4, 7-6 (4) to Canadian qualifier Vasek Pospisil on Saturday night.
It was, without a doubt, the biggest singles victory of his career for Pospisil, who spun around and flung away his racket after smacking a forehand winner to convert his fourth match point.
The Vancouver native's best accomplishment in tennis to date was winning a Wimbledon doubles title with Jack Sock of the U.S. in 2014.
There really was little reason to believe beforehand that Murray would have so much trouble Saturday.
He is, after all, ranked No. 1, owns three Grand Slam singles titles and two Olympic singles golds, has about $55 million more in career earnings than Pospisil and a 45-0 edge in singles trophies.
Plus, Murray had won all four previous head-to-head matchups.
But Pospisil attacked second serves with great success this time and broke Murray four times -- three in the opening set alone -- while also keeping him off-balance with strong net play.
The tone was established early on in the second-round match. Murray, who had a bye in the first round, broke Pospisil twice in the opening set, but gave that edge back each time, winning only 1 of 9 second-serve points in that set.
Pospisil broke again to open the third, then held for 2-0 and had two break points to go up 3-0 after Murray double-faulted for the sixth time. But Murray held there, then broke back, and was steadier until the tiebreaker.
Yet another double-fault gave Pospisil a 3-1 lead, and he stretched that to 6-2, before relenting just a bit on the way to the upset.
Other seeded men losing Saturday: No. 7 Jo-Wilfried Tsonga, No. 19 Ivo Karlovic and No. 30 Feliciano Lopez.
Murray failed to mount the sort of comeback that Venus Williams fashioned earlier Saturday, when she cast aside three match points to get past another former No. 1-ranked player, Jelena Jankovic, 1-6, 7-6 (5), 6-1.
Williams moved into the third round at Indian Wells for the first time since 2001, the year she and her father were jeered after she withdrew from her semifinal against younger sister Serena because of an injury. Williams boycotted the hard-court tournament until returning last year.
Against Jankovic, the 36-year-old Williams -- a seven-time Grand Slam champion and the Australian Open runner-up against her sister in January -- had white tape wrapping her right elbow and left thigh.
And the American, who is seeded 12th, lost the opening set quickly, dropping 16 of 18 points on her own serve, before falling behind 4-1 in the second.
Even after Williams began turning things around from there, she was a point from losing on three occasions, each while she served trailing 6-5 in the second set.
On the first, at 15-40, she ended an 11-stroke exchange with a backhand volley winner. On the next, at 30-40, Jankovic pushed a return of serve long.
And on the third, later in that game, Jankovic again missed a return, again sending it long, and put her hands on her hips.
She would only win one game the rest of the way.
Also Saturday, Madison Keys played -- and won -- her first match of 2017 after time off because of a wrist operation, beating Mariana Duque-Marino 6-1, 7-5. Keys, a 22-year-old American ranked No. 9, had arthroscopic surgery on her left wrist shortly after the season-ending WTA Finals in October.