What is stopping Rafael Nadal from adding another Australian Open title to his collection?

Rafael Nadal's sole title triumph at the 2009 Australian Open wasn't supposed to have happened by any plausible stretch of imagination or logic.

While Roger Federer had seen off Andy Roddick in straight sets in the first semifinal on Thursday, Nadal struggled to beat compatriot Fernando Verdasco in a 5-hour 5-set epic clash which started on Friday and ended in the early hours of Saturday.

The sheer physicality of Nadal's clash with Verdasco coupled with an extra day of rest for his final opponent negated the fact that the Spaniard had beaten Federer in four of the pair's six previous Grand Slam finals.

It was almost a given that Federer wouldn't have had a better chance to exact retribution for the heartbreaking defeat he suffered at the expense of Nadal at 2008 Wimbledon and the rather lopsided hiding he received against the same opponent at Roland Garros a few weeks earlier. But as it turned out, it was not to be.

Nadal, who was supposed to be running on adrenaline alone in the final against Federer, dug into the innermost recesses of his mental and physical reserves to grab the crucial first and third sets against the then 13-time Grand Slam champion. Federer fought back to force a fifth, but Nadal upped the ante to beat the Swiss for a 5th time in a Grand Slam final.

Since that title triumph in 2009, Nadal has been to the Australian Open title match on no fewer than four occasions, but has come up second best each time. In both the 2012 and 2017 title matches against Djokovic and Federer respectively, Nadal led by a break in the fifth set, but was pipped to the finish line.

In the 2014 final, an inspired Stan Wawrinka, who had never managed a set against Nadal in 12 previous meetings, played near flawless tennis to take a two-set lead. Nadal, afflicted by an injury, managed to reduce the deficit but the outcome of the match had become a foregone conclusion.

In 2019 Nadal endured his first straight-sets defeat in an Australian Open final as Djokovic won a record-extending 7th title at the tournament.

2017 Australian Open final

Barring a first round to exit to Verdasco in the first round in 2016, Nadal has made at least the quarterfinals of the Australian Open in each of his nine other appearances at the tournament since his 2009 triumph.

The Spaniard retired against Andy Murray in the 2010 quarterfinals after being two sets and three games down in the third, endured straight-sets defeats to David Ferrer in 2011 and Tomas Berdych in 2015 respectively, and retired down 0-2 in the fifth set of his 2018 quarterfinal against Marin Cilic. In 2020, Nadal's hopes of a title run in Melbourne were ended by Dominic Thiem in the quarterfinals.

There isn't a simple reason to explain Nadal's near misses in Melbourne in 2017 or for that matter in any of his other appearances in the tournament following his run to the title in 2009.

It is a known fact that hardcourt takes a heavy toll on the Spaniard's knees, which bear the brunt of the wear and tear of his body due to the physical nature of his play. Nadal is well aware of that and in recent years has evolved his game in a bid to end points quicker.

The Spaniard has worked on his serve and forecourt skills and has exhibited a greater propensity to end points at the net to complement his solid baseline game.

But with age comes the inevitable slowing down of reflexes. Due to the intrinsic competitive nature of the sport the Spaniard may never explicitly admit this, but it is all too apparent in his recent hardcourt record against his two biggest rivals - Federer and Djokovic.

Nadal has gone 5-0 on hardcourt against Federer since beating the 20-time Grand Slam champion in the 2014 Australian Open semifinals. Against Djokovic, Nadal has failed to win a set in nine matches since beating the Serb in a four-set 2013 US Open final. In fact, outside of clay, Nadal is 0-6 against Federer and 0-10 against Djokovic since his last non-clay wins against the duo.

Entering the 2020 Australian Open, a surfeit of hardcourt matches may have seriously jeopardized the Spaniard's chances of success.

At the 2019 Coupe Rogers, Nadal successfully defended a hardcourt title for the first time in his career. The Mallorcan followed up that success with his fourth triumph at the US Open where he beat Daniil Medvedev in a bruising five-setter - a match which didn't look like it would go the distance when Nadal led by two sets and stood three holds of serve away from the title.

The Spaniard then played a match at the Laver Cup (beat Milos Raonic) but took no further part in the tournament. Nadal skipped the Asian swing and joined the action in Paris where he withdrew ahead of his semifinal against young-gun Denis Shapovalov, owing to an injury.

Following a group-stage exit at the ATP Finals where he failed to reach the semis despite winning two of his three matches, Nadal sizzled on the indoor hardcourts of Madrid, winning all five of his matches as Spain lifted the revamped Davis Cup finals.

In an intense start to the 2020 season, Nadal won four of his six singles matches as Team Spain fell to Team Serbia in the inaugural ATP Cup. That ought to have been an ideal start to the Australian Open. However, a difficult draw which saw the Spaniard go up against combustible Australian Nick Kyrgios and the ever-improving Thiem on meant that a run to the title match was a difficult proposition.

Nadal takes out Kyrgios in four sets in the 2020 Australian Open

And so it proved. Kyrgios came within two points of taking a two sets to one lead and was a tiebreak away from forcing a fifth set before Nadal escaped. But the Spaniard found Thiem a less generous opponent.

Twice the Spaniard was up a break against Thiem in the quarterfinals. He served for the first set and had a set point, and also 4-2 in the second set, but couldn't capitalize on either occasion as Thiem took a two-set lead.

Nadal was now in uncharted territory. Only once in his career had the Spaniard recovered from a two-set deficit to win a match (2006 US Open 2R against Robert Kendrick).

Nadal started his comeback on the right note, breaking Thiem decisively to force a fourth set. But Thiem regrouped after failing to serve out the fourth set by taking the win in the ensuing tiebreak.

With that, Nadal's hopes of becoming the first player in the Open Era to win all 4 Grand Slam tournaments multiple times vanished into thin air yet again.

At 33 Nadal is not getting any younger, and perhaps the Spaniard may never again be the last man standing in Melbourne. But stranger things have happened in the sport, where the indefatigable Spaniard has scripted many an epic comeback in his storied career.

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