John Millman has overcome an early hiccup to advance to the last 16 of the Serbia Open.
The Australian world No.43 dropped his serve early in his opening-round match to go behind but fought back to secure a 7-5 6-4 victory over local wildcard Danilo Petrovic.
Millman created 17 break points and converted four of them, two in each set, in an almost two-hour workout against 157th-ranked Petrovic.
The seventh-seeded Millman entered the clay-court tournament with a 3-8 record this season and is aiming to reach his first quarter-final of the year.
His next opponent will be Uruguayan Pablo Cuevas or Finn Emil Ruusuvuori in the round of 16 of the ATP 250 event.
In other first-round results, Marco Cecchinato, the 2018 Roland Garros semi-finalist, needed just 66 minutes to record a 6-1 6-4 win over Viktor Troicki while Nikola Milojevic was the only Serbian player to record taste success on Monday with an impressive 6-4 6-0 performance against Federico Coria of Argentina.