Mikko Ilonen produced a superb front nine on day two of the Volvo World Match play Championship to lead reigning champion Graham McDowell by three shots.
The Irish Open champion had to respond to his opening-day defeat to Joost Luiten and did just that against a man who has won 15 of his 17 matches in the tournament, which is taking place at London Golf Club.
The Northern Irishman missed from six feet for a birdie to win the first and then saw Ilonen birdie the second after a brilliant approach shot from heavy rough.
Ilonen then holed from 10 feet for another birdie on the third after conceding McDowell's tap-in.
The Finn moved two ahead on the fifth and although McDowell won the next, another Ilonen birdie on the seventh took him two clear once more.
That became three on the ninth as Ilonen made it five birdies from as many par fours, leaving McDowell three behind despite reaching the turn two under.
McDowell's Ryder Cup partner Victor Dubuisson was enjoying better luck against Shane Lowry, who both won their opening matches.
The Frenchman raced into a two hole lead with birdies on the fourth and sixth but then missed the chance to go further clear on the seventh with missed birdie and par putts.
That allowed Lowry to close the gap to one, but the Irishman was unable to respond to birdies on the eighth and ninth and fell three behind.
Stephen Gallacher recovered from losing the first two holes to win three of the next four against Spain's Pablo Larrazábal to reach the turn one shot ahead.
Luiten edged in front in a topsy-turvy clash with Alexander Levy. Only two of the first seven holes were halved, with the lead changing hands three times.
Last year's runner-up Thongchai Jaidee was two down after six against George Coetzee, who had halved his opening encounter with Henrik Stenson.
Francesco Molinari started quickly, claiming birdies on three of the first four holes to move three clear of reigning Race to Dubai champion Stenson.
Stenson pulled one back on the fifth but was unable to recover any more ground before the turn.
Wales' Jamie Donaldson birdied the second to move one up on Jonas Blixt, with the other five opening holes all halved with pars.
The final pair of Paul Casey and Patrick Reed both birdied the opening hole, before sharing pars on the next five holes.
