Thomas Pieters of Belgium shot a 7-under 65 on Saturday to take a one-stroke lead after the third round of the Czech Masters.
Pieters began the round one shot behind overnight leaders Matthew Fitzpatrick and Pelle Edberg but made an eagle on the par-5 first hole and continued with four birdies on the next nine.
He then suffered a blow by dropping two shots on the 11th due to playing a wrong ball in the rough.
Seeking his first European Tour victory at the Albatross Golf course near Prague, the 23-year-old recovered immediately with a birdie on the 12th and added two more on the 14th and 16th for a 17-under 199.
Edberg produced a flawless round of a 5-under with five birdies to sit a shot back.