Kyrgios set the tone by serving underhand to start the match, catching Medvedev off guard. There were also a bevy of drop shots and even a successful through-the-legs effort. "I was trying to throw him off his game because I knew he loves rhythm. He's a great player," Kyrgios said. "Today was a lot of fun. I thought the crowd was a lot of fun. It's very important to go out there and put on a bit of a show."
Medvedev played better after getting his lower back massaged after the first set but had no answer for Kyrgios' wide array of shots in the third, prompting the frustrated Russian to break his racket by slamming it on the dirt.
Kyrgios won the final game at love by serving four straight aces. He had 15 aces in all. Meanwhile, Serena Williams withdrew ahead of her second-round match against sister Venus because of a previously injured left knee.
Also, Joao Sousa saved four match points before beating Frances Tiafoe 6-3, 6-7 (3), 7-6 (4) to set up a meeting with Roger Federer, who made a late decision to play in Rome because he wants more matches .
Italian wild and Rome resident Matteo Berrettini reached the third round by upsetting 2017 Rome champion Alexander Zverev 7-5, 7-5 amid a raucous soccer-like atmosphere on Campo Centrale; while David Goffin rallied past Stan Wawrinka 4-6, 6-0, 6-2.
Others advancing included Karen Khachanov, Marin Cilic, American qualifier Taylor Fritz, Radu Albiot, Jeremy Chardy and Diego Schwartzman. Former No. 1 Caroline Wozniacki retired due to a left leg injury after losing a first-set tiebreaker to American opponent Danielle Collins.
Wozniacki took a medical timeout when trailing 5-2 to get treatment then came back to force the tiebreaker but she quickly retired after losing the set. Wozniacki also retired from her opening match at the Madrid Open last week.
The 30th-ranked Collins notched her fourth victory over a top-20 player this season, with the other three coming during her breakthrough semifinal run at the Australian Open. "I'm comfortable on this surface, and making improvements within my game, and doing a little bit better than I did last year," Collins said.
French qualifier Alize Cornet beat Aryna Sabalenka 6-1, 6-4. Ashleigh Barty, Maria Sakkari, Carla Suarez Navarro and Kristina Mladenovic also advanced.
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