During the four months since Rafael Nadal's closing, charging, vaguely awkward, utterly effective backhand volley went through the court untouched to end the U.S. Open, the 2018 Australian Open promised a Grand Slam unparalleled. It would bring so many returns from so many absences that it seemed primed to take a sport with holes in its draws and stitch the whole thing back together.

Instead, it will settle for being a tour de force loaded with high-level curiosities.

Where once it held the possibility, if not the plausibility, of regathering Serena Williams, Novak Djokovic, Andy Murray, Stanislas Wawrinka, Milos Raonic and Kei Nishikori from all their various hiatuses, it will boast half those six, lacking Williams, Murray and Nishikori because of a blessing, a hip and a wrist.

Williams withdrew after having given birth last September, Murray with the hip injury that short-circuited his 2017 season last July at Wimbledon, and Nishikori with the wrist that has made him inactive on the ATP Tour since last August in Montreal.

That left Djokovic, Wawrinka and Raonic, with Djokovic the most compelling, amid rankings that just look weird for anyone prone to read tennis rankings in recent decades.

Djokovic, with his 12 Grand Slam titles, his record-tying six Australian Open titles and his 223 weeks at No. 1 (fifth-most in the game's history), has spent 18 months as a mystery. It began shortly after he won the 2016 French Open to hold all four Grand Slam titles at once, and it persisted until he finally walked out of Wimbledon during a 2017 quarterfinal opposite Tomas Berdych, his right elbow urging respite.

If he keeps his place in the Australian Open draw after winning an exhibition over Dominic Thiem on Wednesday, he will do so with a quirky seeding of No. 14. He will open a hard road against the American Donald Young, ranked No. 63, and, if Djokovic surpasses that, he would reach probably Gael Monfils and Wawrinka, the latter a three-time Grand Slam champion, 2014 Australian champion and veteran of knee surgery that prevented a title defense last August and September in New York.

Everybody knows that 12 months ago, two players launching comebacks, No. 9 seed Rafael Nadal and No. 17 seed Roger Federer, wound up in the Australian final, with Federer winning a stirring five-set gem, among the reasons the ceaseless rivals are seeded No. 1 (Nadal) and No. 2 this time. Yet nobody knows how any of this year's rusty sorts might function, or how those who have grabbed their formerly unattainable rankings will function with fresh pressure.

Among No. 3 Grigor Dimitrov, No. 4 Alexander Zverev, No. 5 Thiem, No. 6 Marin Cilic, No. 7 David Goffin and No. 8 Jack Sock, only Cilic has reached a Grand Slam final (actually two, with one win). Dimitrov did engage Nadal in a brawl of a 2017 Australian semifinal, falling only 6-4 in the fifth set, and did win the ATP Finals in London in November.

He also ran across a player of intrigue in the run-up tournaments.

On Jan. 6 in Brisbane, Australia, Dimitrov lost a three-set semifinal to Nick Kyrgios, the charismatic, enigmatic Australian whose plight in Melbourne will lure many eyes. Kyrgios, ranked No. 17, won that event in Brisbane and told reporters, "Right now it's all about recovering and feeling the ball for the Oz Open, because obviously I'm playing well under pressure and in high-pressure situations."

While labeling Kyrgios a deserving winner, Dimitrov also told reporters: "We know how he is. He can switch from playing unbelievably to just missing, you know, the easiest shots and all that."

That backdrop has become established enough with Kyrgios that he must be older than 22, but isn't. He, more than any Australian player, will play the lead in a Grand Slam running theme: the extra heaps of pressure upon home-country, home-team players.

No Australian man has won the Australian Open since Mark Edmondson in 1976, and no woman since Chris O'Neil in 1978. Lleyton Hewitt reached the final in 2005, falling to Marat Safin. (In that same category for the other Grand Slams, the French are at a 35-year French Open drought for men, 18 for women; the British at a 41-year Wimbledon drought for women; and the Americans at a 15-year U.S. Open drought for men.)

Williams, not prone to droughts herself, last played last January in winning the 2017 Australian Open, and gave birth to her daughter last Sept. 1. She kept a potential return in play until last week, when she pegged herself as "not where I personally want to be" after playing one exhibition in Abu Dhabi in late December. She wrote in a statement, "My coach and team always said, 'Only go to tournaments where you are prepared to go all the way.' "

That left a raft of highly ranked players who will rummage around for first Grand Slam titles. No. 1 seed Simona Halep, 26, has reached two Grand Slam finals and two semifinals. No. 2 Caroline Wozniacki, only 27 while seeming to have been around for half of forever, has reached two finals and four semifinals. No. 4 seed Elina Svitolina, 23, has found two quarterfinals, while No. 6 seed Karolina Pliskova, 25, has made the quarterfinal or better in four of the last five Grand Slams, a feat in a sport deep in talent and rife with wild inconsistencies.

Tucked between those players are the two 2017 Wimbledon finalists.

The second major incarnation of Venus Williams, operating from a No. 5 seed, also seeks a first Grand Slam title. The first incarnation reaped seven, between 2000 and 2008. Yet a remarkable run has followed a four-year career dip from earlier this decade. At ages 36 and 37 in 2017, with that number changing in June, Williams journeyed to two Grand Slam finals, one semifinal and one fourth round.

"There were definitely a lot of wins this year," she said at season's end in Singapore, "and definitely a lot of wins that were satisfying."

At No. 3, Wimbledon champion Garbine Muguruza will seek to complete three-fourths of the career Grand Slam by age 24, even as few will favor her to do so. Oceania has not been kind to her this January, seeing her withdraw from Brisbane with cramps and from Sydney with an adductor issue.

While reigning U.S. Open champion Sloane Stephens, a breakthrough semifinalist in 2013, will start from a No. 13 seeding, the women's draw will include only two players who have won an Australian Open: No. 22-ranked Angelique Kerber (2016), and No. 47-ranked Maria Sharapova (2008).