(Reuters) - PGA Tour rookie Sam Ryder held the lead on eight-under-par through 15 holes, with Rickie Fowler two strokes back, as the first round of the Houston Open was halted by darkness in Texas on Thursday.
Kevin Tway and Lucas Glover held the clubhouse lead on seven-under 65, while Beau Hossler was also seven-under after 16 holes.
Ryder took advantage of ideal scoring on a day when the start of play was delayed by two hours due to torrential overnight rain that softened the Golf Club of Houston course and prompted officials to allow preferred lies.
Ryder, in his 12th start on tour this season, is among 33 players who will return to complete the round early on Friday.
Tway was quite happy about the rain delay.
"I enjoyed a little bit extra sleep. Sleep's always good for me," he said.
"I played well, kept the ball in play and made a few long putts."
Fowler, the best of the 'big names' with a 66, was satisfied with his start as he gears up for what he hopes will be a breakthrough major victory at the U.S. Masters next week.
"Building confidence for the rest of the week and going into next week," he said.
"I did a good job tee to green (and) it was nice to make some putts. It was fun with the softer greens. You played aggressively even if you did miss the fairway."
Fowler is among 18 players in Houston who have qualified for the Masters. The winner on Sunday will join them, if not previously exempt.
Among other Masters-bound players, Phil Mickelson, Jordan Spieth and Justin Rose shot 68.
Mickelson is not worried about winning in Houston as much as practicing shots he will need at Augusta.
"I'm hitting a lot of the shots that I will use on a few holes next week, these low running slices," said the 2011 Houston champion.
"I'm just trying to hit that shot and get comfortable with it and I hit it well.
"Out here there's potential for disaster on every tee shot
and I have found that disaster over the years just about every place here, so I was able to navigate through all that disaster and didn't hurt myself off the tee."
Spieth said he had found something with his swing after struggling recently.
"I had some really rough range sessions the last two days," he said.
"I started to get a feeling I really liked and I committed the last few holes.
"That was fantastic. I feel good things are coming.
"That was the best first round I've had in a long time."
(Reporting by Andrew Both in Cary, North Carolina; Editing by Peter Rutherford)