The lines to get into Court 17 began long before CiCi Bellis arrived Thursday. Each entrance had hundreds waiting to get in, but the fans already seated weren’t going anywhere. Many of them sat through a five-set men’s match there just to see the 15-year-old Bellis meet Zarina Diyas in a second-round match.

Bellis put on a show even in a 6-3, 0-6, 6-2 defeat.

Former U.S. Open champion Andy Murray was on the Arthur Ashe Stadium court at the same time, but it was Bellis’s match that people watched on the jumbotrons around the tournament grounds.

“This whole experience has been unbelievable,” Bellis said. “It’s been mind-blowing, the best of my life.”

After struggling in the first set, committing 22 unforced errors, Bellis came back with a vengeance to dominate the second set. She smiled during the last changeover in that set, leading 5-0, as fans chanted her name.

Broken early in the third set, Bellis stopped smiling. The crowd kept cheering, “Let’s go CiCi,” as her deficit in the decisive set grew. Bellis was expressionless.

Gibbs reaches third round

Nicole Gibbs, a two-time NCAA singles champion at Stanford, advanced to the third round in the afternoon, upsetting No. 23 seed Anastasia Pavlyuchenkova, 6-4, 6-7 (8-6), 6-3.

Gibbs, 21, served for the match twice in the second set but got broken both times. After dropping the second-set tiebreaker, she broke Pavlyuchenkova in her first service game of the third set en route to the win.

“I would not have described myself as calm after having lost that second set,” Gibbs said.

After becoming the first repeat NCAA singles champion when she won in 2013, Gibbs opted to turn pro instead of returning to school. The NCAA men’s and women’s singles champion receives a wild card to the U.S. Open, and Gibbs lost in the first round the past two years.

This year, she earned a wild card after good results this summer. She beat Melanie Oudin in a Challenger tournament in Carson, Calif., and lost in the final of a Challenger in Lexington, Ky.

She’ll play Flavia Pennetta, a semifinalist last year, in the next round. Gibbs lost to Pennetta in the first round last year. . . .

American Madison Keys, the No. 27 seed, lost to qualifier Aleksandra Krunic, 7-6 (7-4), 2-6, 7-5. The only two seeded American women that remain in the singles field are Serena Williams, who won her match against Vania King, 6-1, 6-0, and her sister Venus.