BEIJING, China - No.15 seed Sofia Kenin reeled off the first six games and the last six games in a row during her clash against 2015 champion Garbine Muguruza - but in between, a late-night roller coaster capped off the last match of Day 1 at the China Open, 6-0, 2-6, 6-2.

“I obviously started out really well in the first set and I knew that she was going to pick up her game,” Kenin told wtatennis.com afterward. “I just felt pretty tired, mentally drained, but I’m happy that I somehow found a way to just fight through it. 

“It was not easy, and she’s such a tough player to play. She played really well, and getting the win against her is obviously really good for me and my confidence.”

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With every single previous match on Diamond Court going three sets, it was just 10 minutes shy of 1:00 am when Muguruza and Kenin took the court for their own first-round clash. 

Kenin seemed totally unfazed by the late start - or by the two-time Grand Slam winner across the net - and took the first set to love in 21 dominant minutes. Muguruza powered her way to break points in the first game, but that would be the only lead of the set as the American found her range. Kenin reeled off six games in a row to take the opening set. 

But Muguruza was far from defeated in the second set, switching up her game plan and stepping into the court with more aggression. Her powerful groundstrokes dictated play, and playing up the middle effectively took away Kenin’s angles. The Spaniard opened the second set with an early break, 1-0, and then extended her lead to 4-1 before serving out to force a tiebreaker. 

Another early break went Muguruza’s way, and the Spaniard looked ready to run away with the score, 2-0. But Kenin raised her level and regained her first-set form, tracking down everything Muguruza sent her way and returning with interest. She reeled off the last six games in a row to put an end to the match at 2:31 am Beijing time and move into the second round.

Sofia Kenin takes the court during her China Open first-round clash. (Getty Images)

“I love China, that’s why [I play so well here]!” Kenin grinned. “Yeah, I feel like I’m having weeks here, I’m really happy. I’m really happy that I’m able to battle through this, I’m literally so drained. But I’m really happy. 

“The support from the crowd was great, even at 2:30 in the morning, surprisingly!”

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Kenin was the more consistent player throughout the three sets, reflected in her 20 winners and 18 unforced errors, serving up five aces and winning 71% of points behind her first serve. On the other side of the net, Muguruza struck 24 winners - the majority of which came during the second set - but was undone by 33 unforced errors and a 51% first serve percentage. As a result, Kenin broke Muguruza six times from 12 opportunities, and Muguruza three from seven.  

Up next for Kenin, the Moscow-born American player will face a Russian opponent in round two as she awaits the winner between Anastasia Pavlyuchenkova and Veronika Kudermetova.