Lee Slattery turned in 33 to open up a one-shot lead midway through the third round of the weather-affected D+D REAL Czech Masters.
The Englishman was one of 68 players to complete their second rounds on Friday before heavy rain flooded the course at Albatross Golf Resort and was at the top of the leaderboard when play resumed at 7.30am.
Chris Hanson had 17 holes to complete and he signed for a 66 to take a three-shot lead which he extended to four in the early stages of his third round but, as he began to fall back, Slattery made three birdies on the front nine to get to ten under.
Countryman Hanson was then at nine under, a shot clear of South African Haydn Porteous and Swede Pontus Widegren.
All three of the final group made birdies on the first in round three with Slattery finding the green in two and James Morrison and Hanson both laying up and hitting excellent approaches into the par five.
Hanson then holed an eight-footer on the second to make it birdie-birdie on the first two holes for the third day in a row, and with Slattery having to get up and down for par, the lead was four shots.
Morrison dropped a shot after finding trouble off the tee and with Porteous making a birdie-birdie start, the South African was in third on his own at seven under.
A poor tee-shot on the fourth led to Hanson taking a drop and when he three-putted to compound the mistake, the lead was down to two shots.
That was then reduced to one on the sixth as Slattery holed from six feet with Hanson doing well to make par.
Porteous continued to make good progress and he hit an excellent tee-shot into the par three seventh to get to eight under.
Hanson appeared to be wobbling and missed the green on the seventh before holing an excellent 15-footer for par. He made another good putt on the next but after a poor tee-shot and approach, that was for a bogey and the lead had disappeared.
Widegren had birdied the first and sixth and when he played a sensational bunker shot on the eighth, the Qualifying School graduate was just one back.
A Slattery birdie meant he was two off the lead, though, as the two-time winner hit an excellent approach to the ninth to get back to the top of the leaderboard.
Tom Lewis had made seven birdies in his last 11 holes of round two to fight back from four over and further gains on the first, second and fifth made it ten for the day.
He then holed a bunker shot on the eighth to get to seven under where he was soon joined by Felipe Aguilar who added to his opening birdie with one on the ninth.
Morrison, Callum Shinkwin, Julian Suri, Martin Wiegele and Jeff Winther were then all at six under.
