MELBOURNE -- Coco Gauff's speed and court coverage is second to none on the Hologic WTA Tour, and the reigning US Open champion proved it again in her second-round win at the Australian Open. 

Gauff's court coverage, speed and discipline were tested against Caroline Dolehide on Day 4. With Dolehide's heavy forehand keeping Gauff on the run, the 19-year-old had to be patient to wait for her opportunities to strike. 

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After coming back to take the first set in a tiebreak, Gauff looked in cruise control in the final game before Dolehide started wiping out match point after match point. To earn her third match point of the game, Gauff dug in to win this 19-shot corner-to-corner rally. Gauff spent the majority of the rally diffusing Dolehide's pace before countering with her own backhand up the line to set up her winning shot.

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Bonus hot shot: More speed from the speedster:

Gauff will face 23-year-old Alycia Parks in the third round. According to Gauff, who has known Parks since she was 9, the first-time meeting will feature two of the best athletes in the women's game.

"Used to practice with her and her sister," Gauff said. "We both lived in Delray Beach, or in that area. I know her very well. I always root for her -- obviously not for the next match.

"She has a big game, big serve, big shots, very athletic. I think she's one of the most athletic players on tour. Like me, her, Sloane and Iga are probably up there, and Sakkari. Those would be my Top 5. She's up there."

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