One day after making a four-hole comeback to win her first-round match, Bonanno upset stroke-play medalist Bailey Tardy, 4 and 3, in Thursday morning’s second round of match play at the 2013 U.S. Girls’ Junior Championship, being conducted at Sycamore Hills Golf Club.

Bonanno, 17, from Norridge, Ill., worked her way to a 2-up lead through six holes. But a mid-round charge from Tardy flipped the match upside down. Tardy stuck her tee shot on the par-3 7th hole and her approach on the par-4 8th hole close, and the resulting birdies pulled her back even with Bonanno.

“I was like, oh no, here we go again,” said Bonanno, who had flashbacks to her own marathon comeback on Tuesday. “To get back to all square, it was not easy. She had to work harder and I had to work hard to keep going.”

Tardy grabbed her first lead with a birdie at the par-4 ninth. The lead, however, was short-lived. Bonanno called the par-4 10th the turning point of the match, as Tardy’s bogey dropped the match back to all square.

“Then she started losing her strokes and I started gaining on her,” said Bonanno, who won four straight holes to wrap up the victory on the 15th green. “Somehow I came through and started hitting shot after shot, sticking it. It just worked out.”

Bonanno will face Mexico’s Maria Fassi, who came back from losing a three-hole lead to eliminate Kristen Gillman, 1 up.

“They've been two matches that were really hard,” said the 15-year-old Fassi, who came back from four holes down on Wednesday to advance. “But I think I can go on and play how I know to play.”

The morning’s final two matches both came down to the final hole. Bethany Wu, 16, of Diamond Bar, Calif., stuck her approach at the par-4 17th to within 5 feet and drained her birdie putt to pull all square with Nicole Morales.

At the 18th, Wu’s birdie attempt broke left, trickling a few feet past. However, Morales put too much power into her par attempt, hitting the hole and lipping out. Wu was able to tap in for par and take the hard-earned 1-up victory.

Wu’s afternoon opponent will be Samantha Wagner, 16, of Windermere, Fla. After hitting her approach to within 10 feet, Hana Ku’s short par attempt at the par-4 18th rimmed out, giving Wagner a 1-up victory.

Defending champion Minjee Lee continued her staunch title defense, shooting the equivalent of six under par (with the usual match-play concessions) in her 4-and-3 victory over Jennifer Peng. Next in the Australian’s path will be 2013 Women’s Open low amateur Casie Cathrea, who survived a tough battle with Jennifer Kupcho to win, 3 and 1.

Yueer Feng, of Orlando, Fla., advanced with a 2-and-1 victory over Emily Campbell. She will face Lee’s countrywoman Hannah Green, who advanced to the third round of her first Girls’ Junior by defeating Sarah Cho, 1 up.

Andrea Lee, the 14-year-old who led after the first round of stroke play, was eliminated 3 and 1 by Maddie Szeryk, of Allen, Texas. Next to face Szeryk is 15-year-old Massachusetts native Megan Khang, who defeated Hannah O’Sullivan in a back-and-forth match that lasted 20 holes.

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