Andy Murray earned his first singles victory at Tour level since January with a three-set win over Tennys Sandgren in the first round of the Zhuhai Championships in China.
Murray, 32, said at the Australian Open that the ongoing problem with his hip could have forced him into retirement.
He instead underwent the resurfacing operation, from which no player has ever returned to play top-level singles tennis.
The former world number one’s comeback initially was in doubles tournaments, including both men’s and mixed at Wimbledon, and he began playing singles competitions at the beginning of August.
The Scot, now ranked 413, won two matches on the lower-level Challenger Tour at the Rafa Nadal Open at the end of last month.
This win over American Sandgren is his first on the ATP Tour since beating James Duckworth at the Brisbane International on 1 January.
He missed the opportunity of a match point in the second-set tie-break, only to race through the decider and complete victory in two hours and 41 minutes.
BBC tennis correspondent Russell Fuller
Murray had to work extremely hard for his first singles win on the ATP Tour since New Year’s Day.
The fourth game of the final set, for example, lasted 19 minutes and 18 seconds.
But Murray was physically stronger than Sandgren in the decider, and his movement, serve and defence were eye-catchingly good throughout the match.
Given the high levels of humidity in Zhuhai, and the two hour 41 minute duration, Murray will be relieved to have a day to recover before the second round.
Especially as De Minaur, the 20-year-old world number 31 from Australia, is an opponent who will make him work very hard, and run a very long way, for victory on Thursday.