Alex de Minor admits that this week the last man of Sydney International is expected to repeat that he would be "dreaming" to win his first senior title.
Australian no. 1 continued its heat for the Australian Open, in which Sydney opener was earning hard on Dussanne Lazovic on Monday.
Before finishing the race for claiming a 6-4, 6-3, 6-4, 6-3 victory over the Ken Roswell Arena, D Minor was hard-working with Serbian World No. 5 in both sets.
The 19-year-old had to face more than three hours of delay.
"The first match of the tournament always works hard, especially against such a high-level opponent. He achieved some quality and played some extraordinary tennis," Minor said.
"The whole day was not easy, waiting around, especially in the early morning and the weather did not allow us to go out and play.
"So how I behaved with the situation and am happy with being really happy with the victory."
D'Menaur, who increased the number of world number 9.9, was the finalist in his home city last year and defending champion Daniel Medvedev returned on Monday and would aim to play one better game.
Medvedev, who defeated Kei Nishikori in the Brisbane final on Sunday, defeated Day Minor in the final last year, and this week saw pair of pair to meet again in Sydney quarter-finals.
But the Australian will now meet the United Nations qualifier Rally Opelka in the second round on Tuesday, with the potential final eight match with Jordan Thompson.
Tennis Australia announced that this year's tournament will be final in its current format after Harbor City won hosting rights for the inaugural ATP Cup next year.
Greek World No. 5 Stefanoos is a favorite of taking the title of men's fiesta.
D is reluctant to take Minor away, but he said it would be "insane" to do as the first title of the final Sydney International title.
"It will be mad, honestly it will be like a dream, but we are still away from it. I have a rival in the second round, which is very difficult."
"I can not look far away. (I am) struggling to be present only. You can not see in the future and can not stay in the past. It is all present and what you do every day.
"I have to focus on that."
Another Australian, led by Matthew Ebden, led a set, he lost his first round match against Argentine Gido Andreszie 6-3, 3-6, 4-6.