Australian golf stars Min Woo Lee and Cameron Smith have surged up the leaderboard to remain firmly in contention for US Open glory in Los Angeles.

Lee fired the low round of the morning, a five-under-par 65, to charge to within three shots of American clubhouse leader Wyndham Clark.

Bidding to join his dual major-winning sister Minjee as a US Open champion, Lee’s dazzling round included an extraordinary 407-yard drive on the 16th hole.

That set up the 24-year-old’s fifth birdie of the day.

Then the Perth prodigy wowed fans with his iron play, knocking an approach at the last to within four feet for a sixth birdie to ice his brilliant round and climb to six under.

“Everything is working pretty good,” Lee said.

“My approach play has been pretty lacking over the last year - or my whole career - so it’s quite nice to actually be in the positives the last two days.

“Hitting it well, driving it well. Driving it a long way actually, which is nice on this course because it’s long.”

Smith is two shots further back at four under after backing up his first-round 69 with a 67 on Friday.

After teeing off on the 10th, Smith dropped a shot early on No.11 before collecting birdies on 12, 13 and 15 to get his round back on track.

The world No.9 picked up two more shots on his inward nine to be well-placed for a weekend challenge.

“I just haven’t been able to hole kind of that 15 to 30-foot range,” Smith said.

“I just need those longer putts, one or two to drop every round, and I’m right

there.”

Lee and Smith entered the year’s third major after career-best results at last month’s PGA Championship in New York and have carried the momentum to the Los Angeles Country Club.

“The turning of the corner probably came a month or so before that,” Smith said.

“I feel as though I’ve been playing good golf now for a couple of months. Just feels really solid. It feels like I’m not doing much wrong.”

Minjee Lee is the reigning Women’s US Open champion and will defend her title next month at Pebble Beach.

Now her baby brother has the chance to complete the first sibling major title double in golf history.

Lee said staying patient was key.

“(I’m) just not making too many mistakes. When I do hit it in the rough, I need to take my medicine and just hit it out,” he said.

Fellow Australian Cam Davis also enjoyed his best PGA Championship yet, sharing fourth to earn a ticket to next year’s Masters, but will miss the cut in LA.

Davis slumped to 11 with a horror 79 and ended his second round equal last in the 156-man field.

Lucas Herbert, Adam Scott and Jason Day all had afternoon tee times.

Herbert was even par and Scott and Day both three over and battling to make the cut.

Clark grabbed the clubhouse lead at nine under with a second-round 67, after opening with a 64 on Thursday.

Former champion and four-time major winner Rory McIlroy is just one stroke behind after a three-under 67.