The Dane had his heart set on making Nick Faldo's team and claims his game suffered as a result of his failure to do so.

The 33-year-old tied for 30th at the British Masters in September then finished a disappointing 13-over-par for joint 131st at the Alfred Dunhill Links Championship in Scotland last month.

Last week he tied for 16th at the Portugal Masters to signal an upturn in fortunes, and he improved even further with an impressive round in Spain.

"For me it was sort of a post-mortem Ryder Cup thing," said Kjeldsen.

"I desperately wanted to get on the team but I didn't make it and it knocked me a bit.

"When I didn't make it maybe I was out there with not the best focus.

"I wasn't sure what I was trying to achieve because the goal was gone. It took me a while to get things into perspective and get on with it."

On leading, Kjeldsen added: "It was a very solid round. I'm hitting it pretty straight especially with my short irons.

"My plan is just to keep playing the same and trust in myself.

"There is a long way to go but today was a great start."

One shot back on six-under were Englishman Richard Finch, Spaniard Ignacio Garrido, Argentinian Angel Cabrera and Swede Peter Hanson, while seven players including Spanish pair Sergio Garcia and Jose Maria Olazabal were five under after rounds of 66.

Tournament favourite Garcia, who is hosting the event at the club he played as a boy and where his father is still a professional, closed his round with three successive birdies.

"Scoring-wise it was good but I know I need to play a little better," said Garcia.

"It feels good playing at home this week. It's good fun. There has been a lot of build-up to it and it's finally here and I was a little nervous this morning."

Two other players on five under are Yorkshireman Simon Dyson and 2002 Open runner-up Thomas Levet, who are aiming for good performances to secure entry to next week's season-ending Volvo Masters.

Only the top 60 players in the Order of Merit gain exemption for the event at Valderrama, and the pair sit 62nd and 61st respectively.

Dyson, who along with Kjeldsen lost out in a play-off to Justin Rose at the same tournament last year, was bullish about his chances.

"Today was the best I've ever played tee to green," he said. "It was nearly a perfect round.

"I gave myself a lot of chances and I didn't ever feel there was a danger I wouldn't make par.

"I've just got to keep taking every day as it comes and if I can carry on playing like this you never know. We'll see what happens."

Finch, who has won twice on the European Tour this year, most recently at the Irish Open in May, was one of a number of players to have a bogey-free card.

"I'm pleased with six under," said Finch, who earned his 2008 tour card by the skin of his teeth last year, rising to 113th after an excellent performance in the penultimate tournament.

"I played well on the front nine but it could have been better.

"I had many opportunities to make birdies. But the most important thing is to keep bogeys off your card."