Herbert clings to share of lead as Ryggs makes charge at Australian Open

Lucas Herbert clung to a share of the lead at his home Australian Open on Saturday as American rookie Ryggs Johnston made a charge in a waterlogged third round and favourite Cameron Smith crashed out of contention.

Overnight leader by four strokes from Johnston, Herbert had a vexing day on the greens in an even-par 72 at rainy Kingston Heath to finish level with Johnston on 14-under (201).

The pair held a two-stroke lead from a clutch of players on 12-under at the sandbelt course in Melbourne including Chilean defending champion Joaquin Niemann and home hope Elvis Smylie, who won the Australian PGA Championship in Brisbane on Sunday.

"Frustrating day, but I haven't gone backwards," said Herbert, who managed one birdie on the par-four ninth to cancel out an early bogey.

"I'm still massively in it tomorrow .... I've just got to stay patient, it's a tournament you really want to win as an Aussie. So it can be easy to want it too much, try to hard."

Johnston, a newly minted professional from Libby, Montana, had six birdies in his first 12 holes to storm into a two-stroke lead ahead of Herbert.

But a poor tee-shot led to a double-bogey on the par-five 15th and he fell back into the lead with Herbert.

British Open winner Smith's long win drought is almost certain to continue after carding a horror 76 laden with five bogeys, leaving him 12 strokes adrift of the leaders.

The former world No 2 came to Australia looking for a first win in nearly 16 months but has missed out in four tournaments.

Bulky home golfer Marc Leishman, a six-time winner on the US PGA Tour who now plays on the LIV Golf circuit, moved into contention with a four-under 68 to be three shots off the pace.