By John Reger

PACIFIC PALISADES, California (Reuters) - Dustin Johnson hit a hole-in-one in pouring rain to upstage fellow American Steve Stricker's green-side theatrics and hold a share of the second-round lead at the Northern Trust Open on Friday.

Both were tied at 10-under par after play was halted at the sodden Riviera Country Club, where failing light left 41 of the field unable to complete their rounds.

Overnight leader Johnson was three-under par with two holes to play, while Stricker made the most of his early start to shoot a six-under 65. Argentina's Andres Romero finished three strokes behind the leaders at one-under with three to play.

Johnson, whose putter lit up the greens to carve a one-stroke lead on Thursday, conjured some magic with his eight-iron on the sixth. His 152-yard tee-shot in pouring rain landed four feet behind the hole then spun the ball back into the cup.

"It was probably my best shot of the day," Johnson said.

"I hit eight-iron and made it, so that always helps the round a little bit."

Johnson had the outright lead until he made his first bogey of the tournament on No. 15. He failed to reach the par 4 in two shots and could not get up and down to save his par.

"It was just kind of a funky stance beside the bunker and chunked it a little short of the green," Johnson said. "I didn't get it up and down."

Stricker lamented the damp conditions, despite handling them with aplomb, and felt lucky to get out early to finish with the day's best round.

"It was pretty miserable out there," the American said. "It never really let up. Conditions probably even got a little worse as the day went on."

Stricker started his round from the back nine in style, sinking a 21-foot putt from off the green to save par. He then chipped in from greenside rough for a birdie on the 18th, his third for the tournament.

He came close to emulating Johnson with his own ace on the fourth, where his tee shot, using a utility club, lipped out to rest less than two feet from the cup.

"A lot of good things happened," he added. "Some of the toughest holes on the course and I'm making birdies. You know, you try to run with it and you're like stealing shots when stuff like that happens."

After a lackluster opening round of 72, Phil Mickelson stormed back into contention with a five-under 66, after finding form off the tee and on the greens.

"I've got to go low (Saturday)," Mickelson said. "I know that, but it's out there if you play well."

American Rocco Mediate and Sweden's Jesper Parnevik withdrew from the tournament citing back injuries, while another American in Chris Couch pulled out after complaining of a shoulder injury.

(Editing by Ian Ransom)