Rory McIlroy's struggles continued in round one of the Scottish Open as Mikko Ilonen produced a flawless performance to surge into a two-shot lead at Dundonald Links.
Blighted by injury problems, McIlroy has yet to win in 2017 - though he does have four top-ten finishes to his name - and has missed the cut at two of his last three events, including at the U.S. Open.
And his form shows no sign of improving after a difficult opening day in Troon, the four-time major winner ending Thursday two over par, nine strokes behind leader Ilonen, who carded a blemish-free seven-under 65.
McIlroy, who started at the 10th, made the turn in 40, bogeying 11 and 12 before an approach that saw him hit into the burn guarding the 13th green result in a double.
A birdie followed but he dropped another shot at the par-five 18th. Gains at three, five and seven left McIlroy one over but a closing bogey proved a fitting end to his round.
Illonen's fortunes could not have been more contrasting, a run of five birides in six holes on his back nine helping the Finn move clear at the top of the leaderboard.
Birdie-- The European Tour (@EuropeanTour) July 13, 2017
Ilonen now leads by two. pic.twitter.com/g6LN7lRk48
Six players are tied for second at five under, with 2015 champion Rickie Fowler clearly unaffected by his U.S. Open final-round collapse, the American two back after a 67.
"It felt good but it's fun to go out on links and for me to hit shots and they don't necessarily have to be spot on," Fowler said. "I felt like I did a good job of hitting fairways, staying on the right side of the hole and made a couple of birdies and it's always nice to have a clean card."
He is joined by McIlroy's player partner Ian Poulter, Padraig Harrington, Andrew Dodt, Paul Peterson and Callum Shinkwin, while Matt Kuchar eagled the 18th to headline a group of six on four under.
Adam Scott is a shot further back after a 69, with world number nine Alex Noren five off the pace.
Noren's compatriot and reigning Open champion Henrik Stenson has work to do if he is to go into his title defence on the back of a good result after going round level par, and Patrick Reed could only match McIlroy's disappointing effort.