Coco Gauff shows more assertive and vocal sides in contentious US Open win over Laura Siegemund

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NEW YORK—“I don’t get tired,” Coco Gauff said during the last tournament she played, in Cincinnati.

That day, she was talking about why she preferred to run the 400-meter dash, rather than the 100-meter dash. But her statement was just as relevant to her 3-6, 6-2, 6-4 win over Laura Siegemund at the US Open on Monday night. Gauff turned the match around because she didn’t get tired, even after a 26-minute game early in the second set, and Siegemund very much did.

Their tense and contentious first-round encounter pitted different ways of winning tennis matches against each other. It was shot-making versus athleticism, and age versus youth.

The 35-year-old Siegemund won the first set with a flawless shotmaking mix. She blended perfectly measured drop shots with well-timed dashes to net. She read virtually all of the 19-year-old Gauff’s passing shots and picked them off for reflex-volley winners. When she put the ball away, she seemed to always have Gauff running in the other direction. When Siegemund closed out the first set with a second service break, a confused hush fell over Ashe Stadium, and Gauff’s coach, Brad Gilbert, stared straight ahead in a rare moment of silence. Was the summer of Coco going to end with a whimper on the first night at the Open?

But even as Siegemund was playing with bursts of energy during the points, she was taking as much time as possible between them. In the opening game of the second set, she finally went over the line and received a time-violation warning. It was a sign that this long game, which would stretch to 26 minutes, was wearing her down. Both players seemed to have staked the match on this game: Gauff earned seven break points, and Siegemund saved every one. Finally, on Gauff’s eighth, Siegemund flagged just enough to send a forehand into the net.

Gauff had broken her serve, and, it turned out, broken her physically for the rest of the second set. Now the American was swinging more freely, while the German was pressing and making errors. Siegemund took as much time as possible between points, while Gauff, urged on by her coach Brad Gilbert, played as quickly as she could. That dynamic boiled over on both sides of the net: Siegemund complained to the chair umpire that Gauff wasn’t giving her time to use her towel between points; Gauff complained that Siegemund was being given too much leeway to play too slowly.

Gauff’s complaint, and the way she finished the match, may have been the most interesting aspect of this match, as far as her future is concerned. The normally level-headed Floridian was more fiery and vehement than usual when talking to the chair. At first, the extra emotion seemed to throw her off. Up 5-2 in the third, with the match seemingly in her pocket, she double faulted three times and was broken. But then, when she served for it again at 5-4, her more aggressive posture was just what the moment called for. She won the first two points by coming to net, and the third with a 114-m.p.h. service winner.

Gilbert has emphasized aggression with Gauff, and it has worked from a tactical perspective. Will it also work from an emotional perspective? More assertiveness is probably good for Gauff’s game, but you also don’t want her to turn her into someone she’s not.

What matters for now is what Gauff said afterward: “I wasn’t playing my best tennis, but I’m happy I got through.”

She’ll try to get through again, with a little less drama, against Mirra Andreeva on Wednesday.