San Francisco Frontiers - Showers produce major drenching at rain-soaked PGA

The reigning Masters champion opened with a bogey, lipping out a 20-foot par putt, as he tried to make a record-tying rally to win a second consecutive major crown.

Second-ranked American Scottie Scheffler, Canada's Corey Conners and 11th-ranked Viktor Hovland of Norway shared the 36-hole lead on five-under 135, but with rain in the forecast all day, their 2:50 p.m. (1850 GMT) tee times weren't going to keep them from getting soaked.

Rahm, who struggled to make the cut, began the day nine strokes adrift, level with the greatest 36-hole win rally in tournament history, managed by Bob Rosburg in 1959 and Bob Tway in 1986.

Jordan Spieth, a three-time major winner trying to complete a career Grand Slam this week, was 11 off the pace after a bogey-birdie-bogey start and a bogey-birdie turn at nine and 10. The American has struggled with a left wrist injury.

Belgium's Thomas Pieters, however, was proving there were strokes to be gained with birdies on four of the first five holes to reach one-over, six off the lead.

His round included 35-foot birdie putts at the par-3 third and fifth holes around a tap-in at the par-5 fourth.

Defending champion Justin Thomas was one-over through eight holes and reigning British Open champion Cam Smith of Australia was one-under after making a nine-foot birdie putt.

Rain was making the thick rough even tougher to escape and reducing length for those fortunate enough to find the fairway.

The par-4 sixth hole, the most difficult through two rounds, had puddles at low points in fairways with squeegees being used to keep the green playable.

Scheffler, last year's Masters winner, would overtake Rahm on top of the world rankings with a victory. He could become the first man to win the PGA and the Players Championship in the same year since Hal Sutton in 1983.

Hovland led after a round for a third consecutive major and was in the top five after 36 holes for his third major in a row. His best major finish was fourth in last year's British Open.

Conners, ranked 29th, is trying to become his homeland's second men's major champion after Mike Weir's 2003 Masters triumph. Conners won last month's PGA Tour Texas Open.

The co-leaders could take some comfort in knowing that all six prior major champions crowned at Oak Hill, including Jack Nicklaus at the 1980 PGA Championship, were in the top three after 36 holes.

Four-time major winner Rory McIlroy, hoping to break that hoodoo, was in a pack on level par, five off the lead. The world number three from Northern Ireland seeks his first major title since 2014.

C.Diaz--SFF