18 July 2010 13:46 GMT

Up ahead, the half dozen or so pairings featuring those players with the most realistic chance of putting the two leaders under pressure were collectively failing to find those much-needed birdies easy to come by early in their rounds.

In fact, none of the later starters were able to take advantage of the better playing conditions that should help make scoring a little easier on the final day. Germany’s Martin Kaymer immediately dropped a shot to par to slip even further behind, while neither Westwood, Canizares, Stenson or American, Dustin Johnson, were able to improve on par over the opening few holes.

Back at the opening hole, Oosthuizen and his closest challenger, England’s Paul Casey, both started with regulation pars as the sharp end of the battle of the Claret Jug got off to a steady if unspectacular start.

Before the final round, Lee Westwood had indicated that his initial battle plan for the final round would be to aim for a solid start and then to play his way into the round. At present it seems to be going to plan with three straight pars going on his card.

After getting off the mark with a par, the Championship leader quickly signaled that he was prepared to take on the flag when the opportunity presented itself. And an aggressive approach shot at the second to 20 feet presented Oosthuizen with a makeable birdie opportunity. Meanwhile his playing partner Casey was dropping his first shot of the day to par and in doing so, he gave the leader a chance to further extend his lead.

On this occasion however, Oosthuizen failed to take advantage of Casey’s error but he carded his second par of the round and marched confidently off towards the 3rd tee.