David Frost from South Africa had two runs of four consecutive birdies in shooting a nine-under-par 62 yesterday to take the halfway lead at the John Deere Classic in Silvis, Illinois.

Two-time champion Frost birdied holes 16 to 18, followed that with another on the first hole, and then gained strokes at the fourth through the seventh to move him to 15-under over two rounds. Tim Herron shot a second-straight 65 to be three strokes behind.

Britain's Paul Curry shot a two-under-par 69 to hold joint-third place. Curry held the lead after the first round on Thursday with an eight-under 63 which was the best score of his career. The 39-year-old had four birdies and two bogeys yesterday.

"I think you have to just take it one step at a time, two rounds of golf," said Frost.

Frost opened his round in the morning on the back nine and shook off surprisingly hot conditions to post his best 18 holes in 10 years. "It was a little hot, hotter at 7:30 a.m. than I thought it should be," said Frost, who shot a 60 during the second round of the 1990 Tucson Open.