It's been a year of mixed fortunes so far for the big four in Men's tennis. Following a French Open filled with drama, the players' grass shoes have been dusted off and the third Grand Slam of the year gets underway at Wimbledon.

Novak DjokovicNovak Djokovic remains world no.1 and took the opening slam of the year whilst Rafa Nadal came powering back at the Serb during the clay court season, romping to his seventh Roland Garros title in Paris a fortnight ago

Meanwhile, Roger Federer has been on an impressive run, despite not quite being able to force his way through in the Slams, and world no.4 Andy Murray continues to struggle with injury and poor results. 

Perhaps a little surprisingly, it's Novak Djokovic who arrives in SW19 as the favourite with the tennis book makers. Djokovic hasn't won a big event since Miami back in March, but he has played in three big finals since and been defeated by Rafa Nadal in each of them. 

Novak will be delighted to finally get away from the clay, feeling that his game is far more suited to defeating Rafa on a faster surface. The Serbian was successful here last year and returns as the defending champion. It's also likely that having finally lost a Grand Slam final and given up the pressure of holding four slams at the same time, Djokovic will more than likely turn up in London confident and hitting freely. 

Following what must have been a truly depressing 2011, Rafa Nadal has bounced back in style this year and although all of the recent success has come on favoured clay surfaces, there is certainly a confidence back in the eyes of the Spaniard, meaning he isn't a long way back from Djokovic in the Wimbledon tennis odds. 

Rafa will be aware that he always has to work so much harder on grass than on any other surface and knows, too, that he has to be at the top of his game just to make it through to the latter stages. The newly rediscovered determination should see Nadal through to at least the quarterfinals, but he won't have things all his own way as he did in Paris earlier in the month. 

Roger Federer hasn't won a Grand Slam for more than two years, and his last success here at Wimbledon came all the way back in 2009, when he sneaked past Andy Roddick in a five set epic. And don't forget, that was the same year Rafa missed the event because of injury. Stil,l just one success short of matching Pete Sampras' record of winning seven Wimbledon titles, Roger is all too aware that time is running thin, and this could well be his last major assault on the SW19 title. 

In fairness to Federer, he has been playing some great tennis since being defeated here by Jo-Wilfried Tsonga in the quarters last year. He held match points in the US Open semis against Djokovic and then went on to win the Paris Masters, the end of year finals in London, the Indian Wells Masters, and the Madrid Masters. 

The most concerning thing for Roger will be his straight sets defeat to Djokovic at Roland Garros a fortnight ago. The Swiss no.1 went out with a whimper and is struggling at make any progress against Djokovic and Nadal in the big Slam events. 

For me, Roger knows he's going to have to put everything on the line here. I don't se him being beaten by anyone other than Nadal or Djokovic this time round. If he can get a bit of luck and only have to face one of those men in the final weekend, this does have the potential to be a glorious Wimbledon swansong for Roger Federer. 

The remaining member of the so called 'big four' is Andy Murray, and whilst a troubling back injury and some very poor form have led many to question if he even forms part of a 'big four' anymore, this is the British no.1's home event and he always does well at Wimbledon. 

Although it is far from his favourite surface and he was carrying an injury, Andy Murray looked confident and played some good tennis on his way to the last eight of the French Open. The concern will be that he lost in his opening grass court match of the season to Nicolas Mahut at Queens and then again he was defeated early on by Janko Tipsarevic at The Boodles event this week. 

With so little grass court practice ahead of Wimbledon, the Scot will have to really turn things around if he's to make it to the latter stages here. As in Paris, Murray should be good enough to feel his way into the event with some fairly easy opponents in the opening couple of rounds. He'll be hoping things quickly start to click into place and by the time he is facing top 20 opponents in the second week, things are back on track. 

A Murray victory here this year is probably less likely than at any other stage in his career, but maybe that slight drop in expectation will help ease the pressure on the world no.4 and enable him to really make some Wimbledon waves. 

In terms of other men capable of winning this event, the very fact that Novak and Rafa have contested the last four Grand Slam finals, won 9 of the last 10 Grand Slams between them, and Federer won the only other, highlights that the chances for the others are very slim indeed. 

Having said that, all runs have to come to an end and there are two or three players that do have the game to win Wimbledon

Jo Wilfried Tsonga is up to no.5 in the world and has been playing far more consistently over the last 12 months. He defeated Roger Federer here last year and held four match points over Novak Djokovic in Paris. Tsonga is an accomplished grass court player and his serve is capable of doing plenty of damage to the top players in the world. 

Tomas Berdych is another man with a devastating serve and he has reached the final here before. Defeated by Nadal in the 2010 final, Berdych did defeat Djokovic in straight sets in the semis. He promised plenty and delivered little in Paris, but I'd expect to se the Czech go deep into the fortnight this time. 

Juan Martin Del Potro is probably the only other man with the game to win this event. It's been a long time since he won the US Open back in 2009 and a year out with injury certainly hampered his progress up the rankings. Del Potro produced a stunning match with Rafa Nadal here just 12 months ago and is playing better tennis this time around. He went two sets up to Roger Federer at the French Open before fading away, but the signs are that he's coming back to his best and he is certainly capable of causing at least one big upset. 

Other players, who won't win but are worth looking out for are up-and-coming Canadian star, Milos Raonic and last year's surprise Aussie package, Bernard Tomic. Andy Roddick is always worth a look but the days of him surprising us with a run right through to the final have probably long gone. John Isner always seemed like he had the potential to be a man for Wimbledon glory but hasn't really made a big impact so far. The big serving American has produced a couple of outstanding results this year, and may cause another upset or two at SW19. 

Verdict

I'm not convinced Rafa will prevail here and fancy he may have some troubles against top 20 players in the second week. Roger definitely has a chance, but for me it would have to be a reinvigorated and pressure free Novak Djokovic to capture a second Wimbledon title

Odds

Novak Djokovic - 7/4

Rafa Nadal - 9/4

Roger Federer - 4/1

Andy Murray - 15/2

Jo-Wilfried Tsonga - 25/1

Milos Raonic - 33/1

Tomas Berdych - 50/1

Juan Martin Del Potro - 50/1

John Isner - 66/1

Bernard Tomic - 80/1

Andy Roddick - 200/1