Golf: Lucas Herbert leads Jason Day by one shot at Australian Open

Jason Day of Australia takes a shot (Reuters)

Sydney: A charging Jason Day drilled a birdie putt just wide of the 18th hole and had to settle for second place behind young compatriot Lucas Herbert at the halfway stage of the Australian Open on Friday.

With Jordan Spieth long in the clubhouse following a disappointing even-par 71 that left him one-under for the tournament, Day launched a back-nine blitz that looked like carrying him into the lead after two rounds of his home Open.

Four birdies in a row from the 12th took the former world number one into a share of the lead but his progress was stalled by a bogey after a poor approach shot at the 17th and the missed six-footer on the final green left him with a 68.

Herbert, unlike defending champion Spieth, had earlier made the most of calmer morning conditions with a six-birdie 66, blemished only by a bogey at his final hole to settle for a nine-under total and a one-stroke lead over Day.

Overnight leader Cameron Davis bogeyed his final hole to drop to third, a shot further back, after a 72, and Anthony Quayle (69) was fourth on six-under as Australians dominated the leaderboard.

"I'm very pleased with the way I played, I gave myself the opportunity again today, made a lot of birdies," said Day, who has never won the Stonehaven Cup and is still looking for his first title of the season.

"I think if I could just tidy it up. I was in a great position at nine-under and going towards the green with the wedge in my hand at the 17th and I just hit a poor shot. Those are the things that frustrate me most."

World number two Spieth had started the day with high hopes of going low on a bright, sunny morning only for his putting game to fail him until the final green, when he finally sank a long putt for his second birdie of the day.

"It was a bit of a struggle today," the American said. "I managed to really stay in it. It could have got out of hand there towards the end.

"To finish strong with a birdie gives me some momentum into tomorrow."

Despite being eight shots off the lead, the 24-year-old Texan, champion in 2014 and again last year, was confident he was by no means out of contention. Day agreed.

"We've got two days left so it's not enough (of a lead) unfortunately," the 2015 PGA Championship winner added.

"He's Jordan Spieth, I wouldn't be surprised to see him pushing for the lead at the weekend. He usually does make a charge at the weekend."