MELBOURNE, Australia — The first tennis player to capture Novak Djokovic’s imagination was a big-serving American with a beautiful one-handed backhand. A grade-school-aged Djokovic, living in the Serbian mountain resort town of Kopaonik, watched on television as Pete Sampras won one of his seven Wimbledon titles, and he fell madly in love with tennis.

“I did not have a tennis tradition in my family,” Djokovic said, adding, “To me it was definitely a sign of destiny to start playing tennis, to aspire to be as good as Pete.”

Djokovic tried to emulate Sampras’s game, right down to the one-handed backhand, before his first coach, Jelena Gencic, encouraged him to switch to both hands because that was his natural stroke. But on other things, Djokovic refused to budge.

Most significantly, Djokovic never abandoned the belief that he would grow up to be the best men’s player in the world, like Sampras, who held the year-end No. 1 ranking for a men’s record six years beginning in 1993, when a 6-year-old Djokovic began playing tennis in earnest.