THE men's singles event at this year's Wimbledon has, on the face of it, a similar look to that of the past half a dozen years.

One of either Novak Djokovic or Rafa Nadal are expected to take the title and the top four seeds comprise the Serb, the Spaniard, Andy Murray and Roger Federer. On closer inspection, though, there's a tangible difference. The big four are more vulnerable than in previous years; those outside the top four now possess a greater belief that they could cause an upset in the tournament.

The most likely result remains that either Djokovic or Nadal will regain the title, though. For too long, the outcome of the grand slam tournaments on the men's side has been acutely predictable. Since the summer of 2005, just two have been won by any player outside of the big four. A changing of the guard may not yet be imminent but one senses it is closer than for some time, and there is one man who is at the forefront of the charge.

Grigor Dimitrov is the 23-year-old Bulgarian who won the Aegon Championship at Queen's Club last weekend, leaving him on the fringe of the world's top 10 at No.13. His victory in London made him the only player to have won titles on every surface this year; he added the Queen's grass court title to his win on hard courts in Acapulco and on clay in Bucharest. Over the last six months he has finally begun to fulfill his widely admired potential.

His rise to prominence has been far from meteoric. Since his mid teens, Dimitrov has been widely viewed as a future star, yet he had not even reached the final of an ATP event before the start of last year. Dimitrov was nicknamed 'Baby Fed' so similar was his playing style to that of Federer, but it was a moniker which he struggled to live up to.

His talent was clear for all to see and, when he won junior Wimbledon in 2008, it was assumed that his transition to senior tennis would be seamless.

Instead, his journey was rocky, with many coming to brand him as another of those unlikely to fulfill their potential. That the Federer comparison followed Dimitrov so closely did him few favours, with the Bulgarian recently admitting his discomfort with it. "At some point, this friggin' comparison with Roger [Federer] came, because everyone was thinking that this is what I was trying to do. I was never intending . . . to look or be like him. But everything that I was doing was turning that way and everyone was putting more oil on the fire," he said.

"I watched all his matches; I'm not going to lie. Young kids have idols, and try to look like them and be like them, but there is a point when you say: 'Screw that; I'm me.' And when you find that, your whole idea and perception of life changes."

There is only so long that a player can be regarded as the next big thing, though; ultimately, he or she must start to deliver. That Dimitrov has finally cast off his shackles is a blessing for every fan. He possesses creative talents that most players can only dream of and appears now to have every chance of becoming a grand slam winner one day.

I have never subscribed to the theory that dominance by just one or two is bad for a sport; to be as consistently exceptional as Nadal and Federer, and latterly Djokovic, is a feat which should be admired in itself. But there can be little argument that the tension has been removed from the early rounds of the major tournaments, so assured is the prospect of the big guns advancing.

There had been hints that others would break the monopoly of the big four. Jo-Wilfried Tsonga, Tomas Berdych and Richard Gasquet were all touted as potential champions only for their challenge to fail to materialise. Juan Martin Del Potro broke the dominance of the top four by winning the US Open in 2009 but has been beset by injury problems ever since.

So Dimitrov's emergence gives men's tennis a welcome injection of excitement. He is more than just a talented player; he is a marketing man's dream. His girlfriend is Maria Sharapova and he was judged by SportsPro to be the world's fifth most marketable athlete of 2014.

He has improved his game markedly in the past 18 months and, with that, his ambition has increased accordingly. Looking ahead to Wimbledon he remarked: "I'd say my goal is to become a member at Wimbledon the easiest way possible; that is to win seven matches."

While this year's Championship is likely to come too early for him to look to winning the tournament, with a favourable draw, he could go far. Every sport needs a superstar. Grigor Dimitrov could be tennis' next one.