Marc Leishman plays his approach shot from the 17th fairway during the third round of the British Open on the Old Course at St Andrews, Scotland, yesterday. The Australian shot an 8-under 64.

History-seeker Jordan Spieth reached the turn in 2-under 34 in the third round of the British Open at St Andrews yesterday as he tried to close a five-stroke gap on halfway-stage leader Dustin Johnson.

The 21-year-old Texan was already aware that there was low-scoring to be had on the Old Course on a cool, damp day in Fife as Australian Marc Leishman charged in with an 8-under 64 just after he had set out.

Spieth had the best of starts with a birdie and, when he added two other birdies at five and seven, he was within two strokes of the leader.

He then missed a short one at the ninth, however, with Johnson having opened his round with four pars, but bounced back with his fourth birdie at 10 to stand two back.

Spieth sees fellow American Johnson as the main obstacle in his path to completing a clean sweep of the year's first three major titles.

He has already won the Masters and the US Open and needs the British Open crown to stand a PGA Championship away from being the first player in the history of the sport to achieve the calendar-year grand slam.

But so far at St Andrews, Scotland, he has played second fiddle to playing partner Johnson, the man he pipped at the post to win the US Open title at Chambers Bay last month.

After two rounds, Johnson led at 10 under, with Spieth five shots adrift and needing a good round yesterday to have a chance in today's delayed finale to the tournament.

He still thinks he can make it three in a row. "I believe I'm still in contention," he said.

"I still believe I can win this tournament. I need a really solid round tomorrow, though, because Dustin is not letting up."

Johnson is the player many believe should have won a major by now, having come close in all four grand slam events, culminating in his three-putt meltdown at Chambers Bay.

But he has looked by far the best player in the field over the first 36 holes at St Andrews.

Now he needs to build on that at the weather-hit tournament.

He headed out in the final pairing of the day with England's Danny Willett, who was one back and inactive since Friday due to the weather.

The 27-year-old from Sheffield was entering unchartered territory, but he says he relished the prospect of becoming the first English winner of the Open since Nick Faldo 23 years ago.

Top Scot Paul Lawrie, the 1999 Open champion, provided plenty for the home fans to cheer about as he stood alone in third at 8 under and a birdie at the third boosted his hopes.

As fate would have it, he was paired with fellow Scot Marc Warren, one of six players tied at 7 under. Warren had a birdie at the second to move to 8 under.

The others starting the day on 7 under were Australians Adam Scott and Jason Day Americans Robert Streb and 2007 Masters champion Zach Johnson, and 2010 Open champion Louis Oosthuizen of South Africa.

Friday's high winds, which forced organizers to announce only the second Monday finish in the event's history, had given way to cool, rainy weather.

The early scoring showed that there were birdies to be had.

Leishman was the biggest mover early in the day with his 64, which could have been even better but for two narrowly-missed putts at 16 and 17.

Last week's Scottish Open winner Rickie Fowler closed in on the leaders with a 66 to get to 7 under, while Jim Furyk had a 66 to land on 6 under.

Another young English player, Eddie Pepperell, double-bogeyed the 17th but still had a 66 to settle in at 8 under.