San Francisco - Phil Mickelson, chasing a 50th career victory, grabbed a share of the lead on Friday in the rain-hit second round of the PGA Tour Pebble Beach Pro-Am.

The 48-year old American, owner of five major titles, added a four-under par 68 at Spyglass Hills course, one of three host courses, to his opening 65 at Monterey Peninsula to move to 10-under par.

He was in the clubhouse on 10-under alongside fellow Americans Lucas Glover (66), Scott Langley (69) and England's Paul Casey (64).

Four-time major-winner Jordan Spieth, the 2017 Pebble Beach champion, was at 10-under through 16 holes at Spyglass when play was suspended for the day due to heavy rain.

Spieth was among 44 players who were to recommence their rounds early on Saturday.

Mickelson, a four-time winner of the event, teed off on 10 and raced to six-under par for his round with six birdies in his first 14 holes.

But he dropped three shots in succession at six, seven and eight -- his 15th, 16th and 17th holes of the day -- before closing with a birdie.

"It was nice to birdie the last, but I hate finishing the round off like that and making three bogeys after having a pretty good round going in," he said.

"I guess to make one on the last -- that was a long, tough hard hole that's usually a driver, eight or 9-iron, and I had to whistle a 4-iron in after a good drive.

"It was just a little bit more difficult conditions today, so I'm also lucky to get done now and get the round," Mickelson added. "Guys unfortunately are still out there playing in some tough stuff."

Mickelson -- who won the tournament in 1998, 2005, 2007 and 2012 -- has 49 wins around the world, including 43 on the PGA Tour. The most recent was his success last in the WGC Mexico Championship.

Casey, 41 and chasing a third PGA Tour triumph, cut a swath through the field, jumping nearly 30 spots thanks to his score of 64 at Monterey Peninsula.

The Phoenix-based Brit teed off at the 10th and produced four birdies and an eagle in a six-hole span. He made one more birdie coming home and completed his round moments before the siren sounded to halt play.

"I played a great round of golf and I'm so happy to get done," he said. "We were on the last hole and I heard that horn go.

"And then there was a second one and then a third one which means, and I had to think for a minute, because you get one long blast, you're done.

"But the three blasts means it's bad conditions, but you can finish the hole and I'm like we can finish the hole? I've never been so happy. I went from upset to happy in an instant."

Spieth, seeking a first victory since his 2017 British Open triumph, ignited his round with five birdies in his first seven holes at Spyglass. He then posted nine straight pars before his day was halted at his 17th hole.

Leading completed scores during Friday's rain-halted second round of the US PGA Tour's AT&T Pebble Beach Pro-Am tournament played at the Pebble Beach, Spyglass Hill and Monterey Peninsula courses (USA unless stated):

Ten under

133 - Phil Mickelson (SH) 65-68, Scott Langley (SH) 64-69, Paul Casey (ENG) (MP) 69-64

134 - Lucas Glover (PB) 68-66

Seven under

136 - Jonas Blixt (SWE) (SH) 67-69, Branden Grace (RSA) (MP) 67-69, Matt Every (SH) 65-71, Brian Gay (SH) 64-72, Kevin Kisner (SH) 65-71

137 - Scott Stallings (PB) 67-70, Rafa Cabrera Bello (ESP) (PB) 69-68

Six under

137 - Talor Gooch (SH) 68-69, Curtis Luck (AUS) (SH) 70-67, Ernie Els (RSA) (SH) 69-68, Kim Si-woo (KOR) (MP) 66-71

138 - Fabian Gomez (ARG) (PB) 67-71