Tommy Gainey, an unheralded American who spent most of last year on a developmental tour, seized a share of the lead on Friday in the second round of the 6.1-million-dollar US PGA Phoenix Open.
Gainey birdied six of the last eight holes to finish his opening round, then fired four birdies against a lone bogey in the first nine holes of his second round before darkness halted play with only six golfers having played 36 holes.
Frost put off the start of the first and second rounds and officials said the finish will be delayed until Monday.
Gainey, who managed a career-best runner-up finish at Disney World in 2008 as a US PGA rookie, played in the final first-round group and shared the lead with countryman Mark Wilson on 11-under-par when darkness fell.
"I've played absolutely terrible," Gainey said. "I'm starting to hit the ball like I'm supposed to. I'm starting to score. Putts are dropping.
"It just so happens that I'm making putts right now and I'm tied for the lead."
Wilson, a winner last month in Hawaii, had only four holes remaining while Gainey still had the front nine to complete.
"We're just going to ride this train as long as I can," Wilson said.
Australian Geoff Ogilvy was third on nine-under-par through 16 holes of his second round. He began a run of five birdies in seven holes on the back nine, his first nine of round two, and had only two holes to play in round two.
Gainey was among 66 players who were unable to complete their opening rounds on Thursday due to heavy frost and unusual cold in the desert region. It caused more than seven hours of delays.
The 35-year-old from little-known Central Carolina Tech opened with a pair of pars Thursday before sunset but returned Friday and birdied the par 5 third, then birdied the par 3 seventh and par 4 11th.
Gainey began a run of three birdies in a row at the par 5 13th and after a par at the 16th finished his round with back-to-back birdies that moved him to the top of the leaderboard after the first 18 holes.