Libietis went a perfect 3-for-3 to start the ITA All-American Championships, winning a pair of singles matches against top-50 opponents and earning a doubles victory with junior Jarryd Chaplin to close the day.
On Friday, Libietis will face qualifier Mac Styslinger of Virginia in the round of 16. Stylinger earned a 6-1, 6-4 victory over teammate at second-seeded Jarmere Jenkins, one of 10 seeded players to lose on the opening day.
After spending the summer months training on the clay courts of Europe, Libietis returned to the college scene Thursday in one of the biggest tournaments of the season and lived up to his No. 13 seeding.
Libietis' day started in the early morning when he defeated 19th-ranked Chris Mengel 6-3, 6-2. The afternoon match proved more difficult. Libietis lost his opening set to 41st-ranked James Chaudry of Mississippi State but picked up momentum in the second set to win 3-6, 6-4, 6-0.
In doubles, Libietis and Chaplin held on for an 9-8 (3) tiebreaker win against Texas San Antonio's Martin Ayala and Diogo Casa.
Sophomore Hunter Reese faced top-ranked Henrique Cunha of Duke in his opening round. Cunha, a veteran senior who has spent nearly his entire career in the top 10, won the match 6-2, 6-1.
Reese dropped into the consolation draw, where he earned a 3-6, 6-3, 6-3 victory over Texas A&M's Shane Vinsant.
In one of the last matches of the day, Reese and senior John Collins were broken late in an 8-5 loss to Mississippi State's Malte Stropp and Jordan Angus. Reese and Collins will play consolation doubles Friday.
ITA All-American Championships
Round of 64
Mikelis Libietis (13), UT, def. Chris Mengel, Duke, 6-3, 6-2
Henrique Cunha (1), Duke, def. Hunter Reese, UT, 6-1, 6-2
Round of 32
Libietis (13), UT, def. James Chaudry, Mississippi State, 3-6, 6-4, 6-0
Round of 32
Mikelis Libietis/Jarryd Chaplin, UT, def. Martin Ayala/Diogo Casa, UTSA, 9-8 (3)
Jordan Angus/Malte Stropp, Mississippi State, def. Hunter Reese/John Collins (3), UT, 8-5
Reese, UT, def. Shane Vinsant, Texas A&M, 3-6, 6-3, 6-3