In professional sport there are levels - with the gap between the great players and the champions often the most pronounced.
In tennis, there have been many top players who have been unable to get over the line and be crowned a champion in one of the four Majors - Wimbledon, the US Open, the French Open and the Australian Open.
We take a look at the best male tennis players to have never got their hands on an elusive Grand Slam title during their professional career.
As far as the current men's game is concerned, there is one name who instantly comes to mind when it comes to discussing the best players yet to win a Grand Slam.
Currently number two in the ATP rankings, Germany's Alexander Zverev has achieved almost everything in the sport bar being crowned a Grand Slam champion - reaching the final of three different majors and even winning an Olympic Gold medal in Tokyo in 2021.
Zverev certainly appears to have all the tools required of a Grand Slam champion - a 6ft 6ins physically robust athlete with a strong serve and well-rounded game.
The German's best chance of Grand Slam success was arguably in his first Major final back in 2020, leading Dominic Thiem by two sets before going down in five.
A two-time ATP Finals winner in 2018 and 2021, Zverev has more than proved he is capable of mixing it with the very best, he is just as of yet unable to get over the final hurdle in the Slams.
Still the only male player to reach number one in the ATP rankings and never win a Grand Slam, Chilean Marcelo Rios was one of the most naturally talented players of his generation.
Relatively small for a professional tennis player at 5ft 9ins, Rios had a wonderful array of shots and terrific court craft.
The only South American male to reach world number one, Rios was renowned for his unpredictability on court - always keeping his opponents guessing with his shot selection.
This maverick style was perhaps his ultimate undoing, with his attitude called into question following a number of misdemeanours on and off the court.
Injuries also took their toll on Rios, who was forced to retire at the age of 27 following repeated back problems.
Rios came closest to being crowned a Grand Slam champion when reaching the final of the Australian Open in 1998, losing in straight sets to Czech Petr Korda.
Very much a victim of the era of tennis he was part of, Spaniard David Ferrer was one of the most consistent players on the ATP Tour during his esteemed career - spending seven seasons in the world's top 10 between 2007 and 2015.
Regularly rubbing shoulders with the Big Three of Roger Federer, Rafael Nadal and Novak Djokovic at their peak, Ferrer was still able to accrue an impressive 27 ATP titles.
Renowned as a clay court specialist, especially in the early stages of his career, Ferrer faced a seemingly invincible adversary in the form of close friend Rafael Nadal at Roland Garros - losing to his compatriot in his only Grand Slam final in Paris in 2013.
Like Rios, Ferrer is 5ft 9ins in height, on the shorter side on the ATP Tour, with his game characterised by his athleticism, never-say-die attitude and the consistency of his shots.
Ferrer's status as one of the most accomplished tennis players to have never won a Grand Slam is underlined by his status as the male player with the most ATP match wins without winning a Major, tasting success on a staggering 734 occasions.
Another player who faced the wrath of the Big Three in his pursuit of Grand Slam glory, Argentine David Nalbandian was one of the fiercest competitors on the ATP tour during his storied career.
Boasting a revered double-handed backhand regarded as one of the best of all time, Nalbandian was a wily operator with an all-court skillset.
Nalbandian's ability is highlighted by a commendable career head-to-head record of 8-11 against the legendary Roger Federer, beating his Swiss rival in five sets in possibly the finest hour of his career in the final of the 2005 ATP Finals.
In 2007, Nalbandian pulled off an unprecedented feat by toppling Rafael Nadal, Novak Djokovic and Federer in the same tournament to claim the Madrid Masters - an achievement which was never replicated.
The Argentine's best performance in a Grand Slam came early on his career, beaten in straight sets in the 2002 Wimbledon final by Australian Lleyton Hewitt aged just 20.
A player who certainly possessed the ability to win a Major, Nalbandian's failure to capture a Grand Slam has been attributed to a number of factors including injury problems, a lack of consistency and a questionable temperament.
A unique figure in a number of ways, Miroslav Mecir became the last player in tennis history to win a tournament with a wooden racquet in 1989 after seeing off Yannick Noah in the final of Indian Wells.
Incidentally, this Indian Wells triumph would be the last title of Mecir's career, with the Bratislava-born sports star forced to retire at the age of just 26 due to lower back problems.
This marked a sad end to what was an exceptional career in which Mecir reached two Grand Slam finals - going down to Ivan Lendl at the US Open and Australian Open in 1986 and 1989.
Dubbed 'The Big Cat' due to his tall 6ft 3ins frame and unusual way of moving and hitting a tennis ball, Mecir's finest career achievement came at the 1988 Seoul Olympics where he secured a gold medal for Czechoslovakia.
An awkward opponent nobody wanted to face during the 1980s, Mecir's victory over Mats Wilander in the quarter-finals of Wimbledon in 1988 was his Swedish opponent's sole Grand Slam defeat in a historic season.
A career cruelly cut short, Mecir's impact on the sport of tennis can never be erased.