Unseeded Australian Jordan Thompson grabbed one of the biggest wins of his career on Friday, ousting third-ranked Stefanos Tsitsipas 7-6 (7/0), 4-6, 7-6 (7/5) to reach the third round of the Indian Wells WTA and ATP Masters.
"It's unreal at a Masters 1000 … to have a win like that is incredible," said Thompson, the world number 87 whose only prior victory over a top-10 player came back in 2017 against Andy Murray at Queen's Club.
He admitted he felt a little lucky when a stinging forehand from Tsitsipas on match point was ruled a hair wide.
"I'm thankful that last ball was out – I thought it was in," Thompson told fans on court.
While Tsitsipas led the third-set tiebreaker 2-1 and 4-3, Thompson's coolness under pressure paid off as Tsitsipas belted a forehand into the net to give the Aussie a match point before succumbing with the near miss.
Thompson next faces Chilean qualifier Alejandro Tabilo, who hung on to beat American Maxime Cressy 7-6 (7/3), 7-6 (15/13).
For Tsitsipas it was another setback in the wake of his sparkling run to the Australian Open final in January.
He departed Melbourne energized despite falling to Novak Djokovic in the title match, but shortly thereafter suffered a shoulder injury.
Playing his first tournament since a second-round exit at Rotterdam, Tsitsipas admitted earlier this week that his shoulder was still troubling him and he didn't have high hopes of a third Masters 1000 crown.
Tsitsipas and women's second seed Aryna Sabalenka – playing just her second tournament since winning the Australian Open – headlined Friday's second-round action.
Sabalenka moved smoothly into the third round with a 6-2, 6-0 victory over Evginiya Rodina, who was playing her eighth match since a return to competition at last year's US Open after three years away from the game.
"Happy to win this match in two sets without struggling too much," said Sabalenka, who has never made it past the round of 16 in the California desert.
Sabalenka, still barred from playing under her native flag of Belarus because of the Russian invasion of Ukraine, next faces Ukraine's Lesia Tsurenko, who beat 29th-seeded Croatian Donna Vekic 2-6, 6-2. 6-2.
In other women's matches, last year's runner-up Maria Sakkari salvaged Greek pride with a battling 2-6, 6-4, 6-0 victory over American Shelby Rogers.
Sakkari, trailing 1-4 when rain halted play for about 90 minutes, managed to turn it around in the second set.
She fended off five break points – despite three double faults – to hold serve in the fifth game and broke Rogers to pocket the set.
The American, who had won all three of their prior encounters, was down 3-0 in the third when she received treatment on her right calf and Sakkari remorselessly powered to the win.
Fifth-seeded Daniil Medvedev, fresh off three straight ATP victories in Rotterdam, Doha and Dubai, continued his red-hot form with a 6-4, 6-3 victory over American Brandon Nakashima.
Medvedev didn't face a break point in the first set, but had to fight off half a dozen in an entertaining second set before closing it out with his third break of Nakashima's serve.
"There were some tough moments in the match, tough break point saves I'm happy that I managed to make it through," Medvedev said. "Second set I could have done better on return a few times to maybe make my life easier, but he also played some great points."
Third-seeded Casper Ruud, former champion Cameron Norrie and 12th-seeded Alexander Zverev all eased into the third round with straight-sets victories.
For Ruud, a 6-2, 6-3 victory over former top-10 Argentinian Diego Schwartzman was a confidence-boosting win in a season in which he had so far failed to advance past the second round in three tour-level tournaments he had played.
For Norrie, however, a 6-2, 6-4 victory over Taiwanese qualifier Wu Tung-lin marked a continuation of the form that saw him reach finals last month in Buenos Aires and Rio de Janeiro, falling to Carlos Alcaraz in the first and beating him in the second.
Germany's Zverev, attempting to rebuild his career after surgery for ankle ligament damage suffered at the French Open last year, breezed past Argentina's Pedro Cachin 6-3, 6-1.