Padraig Harrington failed to take advantage of good scoring conditions at the Portugal Masters with a second-round 72 leaving him nine strokes behind halfway leader, Italy's Nino Bertasio.
Harrington had opened with a four-under-par 67 in Vilamoura, but Friday's card included three bogeys and two birdies to leave him one shot worse off on a day when 44 of the top 50 carded 70 or better.
One of the stranger moments of Harrington's round came at the second hole when he called in a rules official after holing a short putt as his ball had come into close contact with a moth on the edge of the cup. The rules official confirmed that no penalty would be required nor would he have to retake the putt.
Jonathan Caldwell is one stroke behind and in a tie for 37th after a second-round 71 with a bogey on 18 ending his round on a sour note while Cormac Sharvin missed the cut with his 72 leaving him on six over par for the tournament.
Bertasio remains the man to catch, but saw his lead cut in half on day two.
Bertasio was four shots clear of the field after a stunning opening 61 and added a 69 on Friday to post a halfway total of 12 under par at Dom Pedro Victoria Golf Course.
However, on a day of low scoring, former Ryder Cup star Thomas Pieters and France's Matthieu Pavon both shot 64 to reach 10 under alongside Lucas Bjerregaard and Adri Arnaus, who shot 65 and 67 respectively.
Bertasio, who is seeking a first European Tour title, said: "I'm pleased. I couldn't have expected anything similar to yesterday. It was a solid day, I didn't make many putts. The greens were a bit bumpy towards the end.
"I made three birdies out there and they were inside two feet but I'll take it. It was difficult (to stay present) with so many messages and social media but now a good second round in, tomorrow starts the weekend, basically a new tournament and I'm looking forward to it."
Bjerregaard, who won this event in 2017, fired an eagle and four birdies in his 65 as he seeks a third European Tour title.
"There was a little less wind this morning," the 30-year-old Dane said. "Greens were perfect when we started, so that was nice. I took advantage of that and made a few putts.
"It's not been a good year for me. I've not been playing very well. I've had little glimpses here and there of improvement but it's not really shown much.
"These last couple of months I've been playing better and making some more cuts, but it's not quite where it needs to be. I'm pleased with the last couple of days."
England's Richard Bland also shot 65 to lie five shots off the lead, despite struggling with a knee injury.
The 48-year-old, who won his first title at the 478th attempt at the British Masters in May, said: "I'm hobbling around a little bit.
"I've got a tear in my left knee. To be fair, I've been playing with it for most of the season but it's only really been bothering me on the walking side for the last four or five weeks.
"It's getting worse. I'm glad I've got six rounds of the year left to play and then I'm done.
"I can hit balls okay. I'm probably not at full power, but I'm okay. Hitting balls isn't the issue, it's just the walking. Going downhill is the problem when pressure goes on the knee. But making birdies makes it feel a little bit better."