The Australian Open, which started in 1905 - later than all the three other Grand Slam tournaments - was also the last one to open its doors to professionals when it did so in its 1969 edition.
It is the only Grand Slam tournament which has been held twice in one year (1977) and not held in a year at all (1986). Owing to a schedule change which made the Australian Open the last Grand Slam tournament on the calendar, there were two editions of the tournament played in 1977 - one in January and the other in December.
Another schedule change took the Australian Open back to its original January slot in 1987 and to a new venue called Melbourne Park, then called Flinders Park. A year later, the tournament transitioned from grass to hardcourt, leaving Wimbledon as the only grasscourt Major on the tennis calendar.
The first five Open Era winners at the Australian Open (1969 to 1973) did not have a ranking as the ATP rankings only came into being in August 1973. The first World No. 1 to win the Australian Open was Ivan Lendl, who did so in 1990. Since then, there have been 12 other instances of the the world's top-ranked player going all the way in Melbourne.
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Record 7-time winner Novak Djokovic's last 5 titles at the tournament have all come while being ranked No. 1, followed by 3 times from Federer (2006-07, 2010), twice by Pete Sampras (1994, 1997) and once each by the quartet of Lendl (1990), Jim Courier (1993), Andre Agassi (2000) and Rafael Nadal (2009).
Going to the other end of the spectrum, let us meet the 5 lowest-ranked players to have lifted the Australian Open title.
#5 Roger Federer, world ranking - 17 (2017)
Following the first significant injury layoff of his illustrious career, Federer made a dream comeback at the 2017 Australian Open. He ended his 4-and-a-half-year Grand Slam title drought by beating arch-nemesis Rafael Nadal in the final.
Entering a Grand Slam tournament with his lowest ranking (17) since entering 2001 Roland Garros as the 18th-ranked player in the world, Federer dropped a set in his opening round against Jurgen Melzer. He then beat qualifier Noah Rubin and Tomas Berdych in straight sets in the next two rounds.
Federer's first battle of note arrived in the fourth round, where the Swiss maestro recovered from losing the first set in a tiebreak to take a two sets to one lead. After Kei Nishikori took the fourth to force a decider, Federer broke clear in the fifth to beat the player with the best deciding set record in the Open Era.
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In his 13th Melbourne quarterfinal, Federer beat first-time Grand Slam quarterfinalist Mischa Zverev in straight sets to book a clash with compatriot Stan Wawrinka. The more illustrious Swiss looked in control after taking a two set lead, only for Wawrinka to take the next two for the loss of just 5 games to force a decider.
Federer regrouped in the fifth to maintain his perfect record against Wawrinka outside of clay, and book a first Grand Slam final meeting with his arch nemesis Rafael Nadal since Roland Garros 2011.
A dream title match between the two leading all-time Grand Slam titlists lived up to its billing as both men exhibited their best play in different moments of the match to ensure a fifth set - where Nadal survived break points to open up a 3-1 lead.
Just when it looked likely that Nadal would continue his unbeaten Grand Slam run against his Swiss opponent stretching back to the 2007 Wimbledon final, Federer came roaring back into the contest.
The 35-year-old reeled off the final 5 games of the match to win his 5th Australian Open title and a record-extending 18th at a Grand Slam tournament. With the win, Federer returned to the top-10 of the world rankings.
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#4 Thomas Johansson, world ranking - 18 (2002)
Sweden's decade-long wait for a men's singles Grand Slam champion since Stefan Edberg lifted the 1992 US Open title was brought to an unlikely end by Thomas Johansson at the 2002 Australian Open.
The weight of Swedish expectations for a Grand Slam champion had downed Thomas Enqvist in the 1999 Australian Open final against Yevgeny Kafelnikov, and did the same to Magnus Norman at 2000 Roland Garros against Gustavo Kuerten. The country yearned to return to the good old days of Bjorn Borg, Mats Wilander and Stefan Edberg, who captured 24 Major titles between 1974 and 1992.
For a player who never made it past the Australian Open third round in seven previous appearances at the tournament, Johansson exceeded expectations merely by reaching the second week in Melbourne that Australian summer. But the fortnight was to get better still for the Swede.
Johansson beat Romania's Adrian Boinea in the fourth round and fellow countryman Jonas Bjorkman in the quarterfinals to reach his first Major semifinal, where Czech Jiri Novak lay in wait. After taking the first set on a tiebreak, Johansson spectacularly unravelled in the next two sets as he won a combined four games to concede a two sets to one lead.
But the Swede regrouped in time, claiming a hard fought five-set win with his fourth match point to reach his maiden Major final.
In a competitive title match against 2000 US Open winner Marat Safin, Johansson lost his serve twice in the opening set as the tall Russian took a one set lead. Thereafter Johansson took control of the contest, as Safin ceded the initiative to his inspired opponent.
Johansson's backhand and return of serve coupled with the seemingly disinterested Safin's flurry of unforced errors meant that the former became the first 16th seed to win a Grand Slam tournament, and the lowest ranked player to win a Major since 66th ranked Gustavo Kuerten's triumph at Roland Garros 1997.
With the win, Johansson broke into the top 10 of the world rankings for the first time.
#3 Johan Kriek, world ranking - 19 (1981)
Johan Kriek had his finest hour at the 1981 Australian Open as he beat American Steve Denton in the final to become the first South African player to win a Grand Slam tournament in the Open Era.
The Australian Open in those days used to be held on grass at the Kooyong Arena, and was a 64-player draw.
Kriek dropped his only sets before the final against New Zealand's Chris Lewis in the fourth round. He then beat Timothy Mayotte in the quarterfinals and 1976 champion Mark Edmondson in the semifinals to arrive in his first Major summit clash.
In the final against Denton, Kriek delivered a four-set win to become the first player from the African continent to triumph at a Major. The win ascended the 19th ranked Kriek to a career-high 13th in the world rankings.
Kriek played his last Major at the 1982 Australian Open, which he won, in the process joining a select group of players to have won their last Grand Slam tournament.
#2 Brian Teacher, world ranking - 20 (1980)
The 26-year-old, playing his 16th Grand Slam tournament, needed respective four set wins over Australians Paul McNamee and Peter McNamara to book a maiden Major final against another Australian Kim Warwick.
Teacher completed a 7-5, 7-6, 6-3 win to earn the biggest pay cheque of his career and become the then-third lowest ranked player (20) to win a Grand Slam tournament. The 26-year-old then combined with countryman Mark Edmondson to lift the men's doubles title, thereby joining a select group of players to win both the singles and doubles titles at the same Major.
The win helped Teacher ascend to a career-high of World No. 12 in the ATP singles rankings.
#1 Mark Edmondson, world ranking - 212 (1976)
212th-ranked Mark Edmondson scripted a fairy-tale run to the 1976 Australian Open title.
Making only his third Major appearance and second at the Australian Open in 1976, Edmondson dropped two sets against Austrian Peter Feigl in the first round. He then lost a set apiece in respective second and third round wins over Philip Dent and Brian Fairlie to reach his maiden Grand Slam quarterfinal.
It was an all-Australian quarterfinal lineup, and Edmondson won his against Dick Crealey in straight sets. He then beat top seed and two-time champion Ken Rosewall in a four-set semifinal.
In the title match against two-time defending champion John Newcombe, there was little indication of the gargantuan upset in store when Edmondson lost the first set in a tiebreak. But Edmondson reeled off the next three sets 6-3, 7-6, 6-1 to script one of the biggest Grand Slam upsets in the Open Era and become the lowest ranked player to lift a Major title. Edmondson also remains the last Australian player to win the Australian Open.
The win lifted Edmondson from 212 to inside the top 40, at No. 37. Since Edmondson's epic run to the title, only one player ranked outside the top-100 has won a Grand Slam title - 125th-ranked wildcard Goran Ivanisevic, who beat Pat Rafter to win Wimbledon in 2001.