Serena Williams had to pass the torch to somebody and the likeliest candidate, 18-year-old Coco Gauff, is grabbing it. 

Gauff, the 12th seed, is in uncharted territory and embracing the big stage that was all hers on Arthur Ashe Stadium on Sunday. The 24,800 fans have transferred their cheers from Serena to Gauff. 

The crowd chanted, “Let’s Go Coco” as Gauff closed the second set by winning four straight games. 

“It feels insane,” Gauff said. “Fans chanting my name. I was trying not to smile on the changeover. Inside I was trying so hard not to smile. This is a surreal moment for me, on Arthur Ashe Stadium people are chanting my name.” 

Rallying from a 5-4 deficit in the first set and 5-3 in the second set, Gauff powered up with big closes. She’s advanced to her first U.S. Open quarterfinal with a 7-5, 7-5 victory over China’s Shuai Zhang. 

Gauff was her charming, animated self, gyrating and fist-pumping after key game wins. After one long rally late in the second set, she seemed to wag her finger in Dikembe Mutombo style after a block. Gauff said it was something else. 

“That was supposed to be a period, like City Girls period,” Gauff said laughing, referring to the hip-hop group. “City Girls. It’s a City Girl Summer, period. I wasn’t thinking about Mutombo when I did that. I feel like a wall out there, she was running me so much. It’s like you can’t get past me.’’ 

The Delray Beach, Fla., native admitted there’s something about playing in New York and she’s been on Ashe Stadium in all four matches. 

“It’s feeding off the crowd,” Gauff said. “I told my team after the match, for some reason I’m so much more animated. I found like a chill. I think it’s balancing them both. I think New York is bringing out a side of me that I haven’t had since I was 15 so it’s nice.” 

Gauff has played here since she was 15, but her best U.S. Open showing was reaching the third round. She admits maybe the late-set comebacks wouldn’t have been in the cards a few years back. 

“I think it’s definitely being mature,” Gauff said. “I always realize the importance of every point. Even sometimes if you lose a set, if you come back from 4-1 and give that person a hard time, it mentally does something to the other player.’’ 

Now she will face red-hot 18th seed Caroline Garcia, who has had a big hard-court summer and captured the last Open tuneup in Cincinnati. 

“She’s probably playing the best tennis she’s ever played,” Gauff said. 

Gauff’s sheer power rose as the match wore on. Her speed was electric. In the second set, she sprinted in for a drop shot and reached it with her backhand, feathering it crosscourt for a beautifully angled winner. The fans made the place sound like Serena had done it. 

However, Gauff got off to a shaky start. She got broken in her first service game after flubbing two straight shots — a backhand wide and forehand in net. Zhan got up 2-0 but Gauff broke back immediately when she crushed a forehand down the line on break point. 

At 5-4, Gauff was serving to stay in the set and she smashed two service winners to get to 5-5, then broke Zhang to go up 6-5. On break point, Gauff overwhelmed Zhang with a powered backhand and a flustered Zhang hit a backhand long. 

Coco closed the set on her serve to reel off three straight games and the fans were in a joyous uproar. 

The second set looked precarious with Gauff down a break at 5-3 but she again rallied to win four straight games. 

Coco did it in style — like Serena did so many times. Over the weekend after Serena ended her career, Gauff tweeted: “Serena, THANK YOU. It is because of you that I believe in this dream. The impact you’ve had on me goes beyond any words.” 

And that impact might show up again Tuesday.