Alexander Zverev was made to work hard by Viktor Troicki before battling into the second round at the Erste Bank Open in Vienna on Monday.
The world No 5, a five-time title winner this season, recovered after a second set wobble to progress 6-3 4-6 6-4 in one hour and 44 minutes over the Serbian world No 48.
The German 20-year-old top seed has enjoyed an impressive season and thanks to his consistent performances on tour will make his maiden appearance at the ATP World Tour Finals next month, live on Sky Sports.
There were also opening-round wins for Gilles Simon and Richard Gasquet over Latvian wildcard Ernests Gulbis and Spain's Feliciano Lopez respectively on the final week of ATP 500 tournaments of the campaign.
Simon, who will face Zverev next, progressed with a 6-3 6-3 victory in the opening match of the day, while Gasquet enjoyed a comfortable 6-2 6-3 win but there was an early exit for fifth seed John Isner after the American fell to a 6-7(5) 4-6 loss to Germany's Philipp Kohlschreiber.
"I played my best tennis with my back to the wall," Kohlschreiber said. "Though it is rare that a player like him would give a match away once he is two breaks up."
French qualifier Pierre-Hugues Herbert also progressed with a 7-6(4) 7-5 victory over Australian Bernard Tomic and will meet Kohlschreiber in the second round.
Meanwhile, at the Swiss Indoors in Basel, sixth seed Roberto Bautista Agut eased to a 6-0 6-3 victory over Mikhail Kukushkin to progress to the second round.
Denis Shapovalov, the world No 49, fought back from losing the opening set to record a 4-6 6-2 7-6(3) success over Japan's Yuichi Sugita.
The Canadian, who reached the fourth round at this year's US Open at Flushing Meadows, will feature at next month's inaugural Next Gen ATP Finals in Milan, live on Sky Sports, following a hugely impressive second half to the season which included a run to the semi-finals of the Rogers Cup in Montreal.
Sky Sports will have all the action from the Erste Bank Open in Vienna and Swiss Indoors Basel before the Paris Masters.
The Next Gen ATP Finals in Milan and season-ending extravaganza World Tour Finals at London's O2 in November end another memorable year which will be covered via our website sky.mnosports.com/tennis with live blogs and updates as the season reaches its climax.
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