Playing at the Dan Magill Tennis Complex on the University of Georgia campus, Puetz produced a 7-5, 7-6 victory to set up a match with Michael Shabaz of Virginia, who is ranked 11th nationally in singles.
Puetz, who is ranked 16th in singles, improved his record in singles this season to 20-6. "I'm very excited to advance in the tournament and I'm happy with the way I'm playing," Puetz said. "It was a tight match and Williams played very well. I'm having a great season at Auburn and hope to keep it going."
Puetz's next opponent is 17-3 this season and Puetz and Shabaz have never played each other.
"It was another solid win for Tim," Auburn coach Eric Shore said. "He came from behind in the second set to get the job done and he is ready for another tough match tomorrow. Tim has the ability to do a lot of damage in this tournament and he is proving it this week."
Puetz and his partner, Alex Stamchev, were eliminated from the doubles competition in the second round of the tournament.