Wozniacki proved that dedication and patience can result in Grand Slam glory. (AP)

At the 2016 US Open, a world No. 74-ranked Caroline Wozniacki wasn't denying retirement rumors. Though just 26, she was many years removed from her days at No. 1—a distinction that carried its own unwelcome weight.

In her 67 weeks at No. 1 between 2010 and 2012, she was Grand Slam-less, a fact she was reminded of at each turn. The pressure took its toll. Beginning in 2012, amidst cries that she’d never be able to counterpunch her way to a Grand Slam title, she tried to change her game under the tutelage of coaches other than her father and long-time coach Piotr. The results were disappointing.

She did enjoy a resurgence in 2014, reaching her second US Open final, but it turned out to be fleeting. Injuries and plummeting confidence saw her crash out of the Top 50 just before retirement talk reared its head in the fall of 2016. Wozniacki began her rise back up with a run to the semifinals in New York. In 2017, she'd reach six finals before winning titles in Tokyo and Singapore (her biggest yet). But Slam glory still escaped her. 

When she was down two match points and 5-1 to Jana Fett in the second round of the Australian Open, it looked like another Grand Slam disappointment was inevitable. But the Dane persevered. It marked a turning point in her fortnight.

 

Celebration day today????????

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In the end, Wozniacki did in fact counterpunch her way to her first Grand Slam title. She won the title by being herself, and she did it with Piotr at her side. She has returned to world No. 1. Only this time, there’s no debating whether she deserves it.

Though separated by 19 Grand Slam titles, Roger Federer, too, confessed to some doubt that he’d ever get here. Only days before dispatching Marin Cilic for his 20th Slam title, Federer was reflecting on No. 18, which he picked up in Melbourne last year. 

 

Love is in the air down under????????????#RF20

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He admitted that for a long stretch, he thought Rafael Nadal and Novak Djokovic had “blocked” him from ever reaching a magical 20th Slam title. In the five long years he went without winning a Slam, he said he was hoping to get just one more.

Now, as his younger rivals struggle to get their bodies to 100 percent, Federer is staring down a return to world No. 1. He would be the oldest ever at the age of 36.