Smith, the No. 15 seed in the 64-player bracket, will face the No. 47 seed, Tyler Akabane, in Friday morning's second round.
Akabane, who will be a sophomore at UCLA this fall, had an accomplished junior career, qualifying for the 2017 and 2019 U.S. Women's Opens and three U.S. Women's Amateurs before starting college.
Smith has been pretty good, too, and needed all of her talents Thursday.
Yu, who will be a senior at Vanderbilt, won four of five holes early in the round to take a 3-up lead through six.