Dominic Thiem accomplished his main objective at the Argentina Open, getting his first win of the year after an abdominal injury and struggles with his form. (More Tennis news)

Thiem, the 2020 US Open champion whose career-best ranking is No. 3, entered the tournament at No. 99 and said he feared losing his safe spot at top ATP tournaments if he continued to fall in the rankings.

The 29-year-old Austrian beat seventh-seeded Alex Molcan 7-6 (4) 6-3 in the clay-court tournament on Tuesday. Thiem will face Juan Pablo Varillas in the second round.

Thiem won at Buenos Aires in 2016 and 2018. More recently, he was eliminated in the first round of the Australian Open by Andrey Rublev.

This year's defending champion, Casper Ruud, is skipping the tournament. The top attraction is second-ranked Carlos Alcaraz, who will face Laslo Djere in the second round on Wednesday.?