The sub-plot of the PGA Championship in all even-numbered years is that of Ryder Cup contenders jostling for position.

Come Sunday night, Jim Furyk will know the names of his eight American qualifiers. And although it will be over three weeks before his European counterpart Thomas Bjorn is in the same position, this is the biggest remaining chance for the players either to cement their place in the team or make a big move.

Realistically, only Webb Simpson is vulnerable of the players currently occupying the automatic spots for the USA. And his European equivalent is Paul Casey, whose place is currently under threat from the likes of Ian Poulter and Thorbjorn Olesen.

Ryder Cup contenders Poulter Olesen

But while the hitherto-in-form Dane struggled to a three-over-par 73, Poulter, whose last Ryder Cup appearance came at Gleneagles four years ago, was racing to the top of the Bellerive leaderboards.

This is the fifth successive week the 42-year-old has been in action. So far the results have been solid but frustratingly unspectacular.

He was 30th at the Scottish Open, missed the cut at Carnoustie, came in 12th in the Canadian Open and 10th at last week’s WGC Bridgestone Invitational.

He prepared for this week in unusual style – returning home to Florida for a couple of days before travelling to St Louis early on Wednesday morning. That was partly to spend some time with his family, partly for a break from the grind and partly because he had seen the forecast for storms in Missouri on Tuesday.

Either way, it didn’t seem to do his chances any harm as he birdied three of his first six holes to take the early lead. Two shots were given back before he rallied to birdie the 7th and 8th, his 16th and 17th, to post a 67 and take his place on the first page of the leaderboard.

At this stage, he is playing on auto-pilot, but, Poulter being Poulter, there is a certain event that is dominating his thoughts. Needless to say, he knows exactly where he stands in the qualifying race compared to the other Ryder Cup contenders.

“Putting myself on the board is great,” said Poulter. “It’s great for your adrenaline. It’s great for your mindset. It’s good for your confidence levels, and it keeps edging me closer to making the Ryder Cup team. There’s definitely a lot of energy to come from that.

“I’m close, but I need a little push. So, if I can push this week and if I can have a strong week in New Jersey as well and edge in, it would be fantastic.

“I’m close enough now where one good week in the next two weeks can push me in. So I’m close. It’s on my mind. I want to be there in Paris. So hopefully we can make it,” he said.

Ryder Cup contenders Poulter Casey

He is in ideal shape, and with his 2008 team-mate Casey struggling this week, who would bet against him hauling himself up on the world ranking list and into the automatic places?

Poulter, who won the Houston Open in April, is bidding to make a fifth Ryder Cup appearance, having missed out at Hazeltine two years ago.

As for Casey, the most recent of his three Ryder Cups came as long ago as 2008, when Poulter was making his debut. Unfortunately, he found himself five over par after five holes on Thursday – it is a long way back from there in a major championship.

Both he and Olesen have much to do just to make the weekend, let alone earn significant ranking points in the battle of the Ryder Cup contenders.

While the self-styled postman looks well-placed to make a significant delivery.