The 2011 Open Championship is now in full swing (pun intended) and, after 36 holes, the leaderboard is beginning to take shape. Now is the time to analyse who could potentially be lifting the Claret Jug on Sunday night and it is difficult to look beyond US Open champion Rory McIlroy, who is poised three strokes behind current tournament leaders Darren Clarke and Lucas Glover.

The Northern Irishman carded a 69 this afternoon, to leave him on level par for the tournament but McIlroy's scorecard only tells half the picture. The 22-year-old was superb from tee to green today. He made four birdies but he missed at least half a dozen putts by inches and on another day he would have been looking at a round in the low 60s. This was made all the more impressive by the fact that so few players scored well. US Masters champion Charl Schwartzel, Frenchman Raphael Jacquelin and tour veteran Tom Lehman shot 67 but that was as good as it got on a difficult day at Royal St. George's.

Scoring has been especially tough for McIlroy this week as he has suffered from a bad draw. He was out early on Thursday, when the course was at its toughest, then late today, when the winds had built up to 25 mph in places. Despite this the youngster looked composed and comfortable throughout and one senses he has a big round in him tomorrow and, having dealt with awkward weather already, he may be one of the best suited to survive any potential downpours. He is currently 9/1, at totesport, to be Open champion and if there was ever a time to back the Northern Irishman, it is now.

His toughest challenge may not come from his compatriot Clarke (14/1, bet365) but from world number three Martin Kaymer, who is currently just one shot behind the leading duo. The German, like McIlroy, produced some outstanding iron play today and, also like McIlroy, was let down by his putter at times. He is the reigning USPGA champion and he will certainly not be fazed by any pressure of being in one of the day's final groupings on Saturday. It is 13/2, at William Hill, that Kaymer wins the Open and those who like to hedge their bets would be advised to put a saver on the 26-year-old.

It is difficult to make a case for many of the other players at the top of the leaderboard at this stage as consistency is likely to be a problem Thomas Bjorn (25/1, bet365) fluffed his lines today with a two over par 72, while Chad Campbell (28/1, Sky Bet) has failed to finish in the top 40 at any major since his second at Augusta in 2009. Lucas Glover (16/1, bet365) has similarly suffered in the last two years although the fact that he has won the US Open show that he has the temperament to triumph at the top level.

The only players that make real appeal at double figure odds are Charl Schwartzel (14/1, bet365) and Dustin Johnson (20/1, Sky Bet). Schwartzel won this year's US Masters and he has finished in the top 20 of each of his last five major tournaments. His iron play was excellent today and he will be brimming with confidence ahead of tomorrow's round. The South African is definite each-way value and even money quotes on betfair on a top 10 finish look fantastic. 

Johnson is similar to Schwartzel in that his form in the biggest events has improved dramatically over the past two years. The American has three top 10 and five top 25 finishes in his last eight majors and 2/1 on betfair that he makes the top 10 is also worth taking.

Win Market - Rory McIlroy (9/1, totesport) 

Win Market - Martin Kaymer (13/2, William Hill)

Top 10 Finish - Charl Schwartzel (Evens, betfair)

Top 10 Finish - Dustin Johnson (2/1, betfair)