Federer, Nadal and Djokovic have dominated tennis for well over a decade and have amassed 50 Grand Slam titles between them.
Murray also had a brief time at the world No 1 spot after winning three major tournaments.
All four players have surpassed 31 years of age and are considered to be coming towards the latter end of their careers.
But despite their ageing bodies, they are still the figureheads at the top of the sport and they continue to win all the Grand Slam titles.
And because the quartet are still a class above the rest of the pack, Petchey believes they deserve much more credit than they currently get.
“They are actually playing longer. It was almost inevitable the players were going to start getting injuries,” Petchey said.
“You have got the ‘big four’, who are now all in their 30s, so it is unsurprising.
“The fact that they are in their 30s means it should be more celebrated that the tour, with some of the changes they have made, have actually kept these players on tour more.
“Previously we played five sets in the Masters 1000, the players played a lot more doubles of course because they were trying to manage making enough money.
“I actually think a lot of people are making a big deal about it rather than focusing on the fact that Roger is still out there.”
Nadal is celebrating an important anniversary today as it is a decade since he first rose to the top of the world rankings.
And 10 years on he is back at the top of the pile – which deserves a special mention.
“Most people had Rafa done before he was 30,” Petchey added.
“He is still out there and likely to be the year-end world No 1 so I think people have got to take a whole different perspective on where these players are actually at in their careers.”