It's often said that Roger Federer is one of, if not the, greatest tennis player of all time.

He has won more Grand Slam tournament single titles than any other men's singles player, he's won ATP Player of the Year five times, and was ranked among the top eight players in the world continuously for over 14 years from 2002 to 2016. 

In 2012, an article was published by Bleacher Report titled: "10 Records Roger Federer Will Never Equal or Break."

It ran through a list of 10 achievements which, 7 years ago, it was largely unforeseeable that Federer would ever accomplish.

These records include; most year-end #1 rankings, most career singles titles, most single-season match wins, most tennis match wins, most titles won per season, most Grand Slam singles titles, most Grand Slam appearances, most match wins at Grand Slams played on grass, winning a career Golden Slam and finally, winning a calendar year Grand Slam. 

While at the time of writing the article, these records seemed unbeatable, the 38-year-old has already managed to break two of them.

The article argues that it would take until Wimbledon in 2014 to tie with Andre Agassi for second place in the most Grand Slam appearances, but that if he wanted to pass the number one at the time Fabrice Santoro, Federer would have to "remain fully active until the Australian Open in 2017 to reach Santoro - the 2017 French Open to pass him."

They admit that "Federer might do it because there is always that possibility," but they seemed relatively sure that he might suffer an injury or illness to keep him out of Grand Slam competitions in the future. 

Despite both a knee and back injury in 2016, Federer now holds the record for the most Grand Slam appearances, featuring in an incredible 78 Grand Slam singles matches, eight more than former number one Santoro.

The second record to be broken by Federer on this list is the most match wins at Grand Slams played on grass. 

At the time, Jimmy Connors held the record, having won 106 Grand Slam matches on grass, with Boris Becker in second place at 77. Federer was tied with John McEnroe at third place, with 66 major match wins on grass. 

According to the article: "It would take Federer another six years winning titles at Wimbledon to surpass Connors.

"Federer would be 37 years old.

"Chances are rare that Federer will ever break Connors' stranglehold on this record."

Yet, here we are today, with Federer aged 38 and making it to the final of Wimbledon, putting on a very impressive performance throughout the tournament. 

Federer went above and beyond all expectations and now holds the record for the most wins at Grand Slams played on grass. 

In the words of the original article, "time will tell." Indeed it has.

Earlier this year, Federer revealed that he has no plans to retire anytime soon, so who knows how many more of these 'unbreakable' records he might break?