Richie Ramsay says it is difficult for any player in the world to compete with Rory McIlroy when the Northern Irishman is playing his best golf.
Leader McIlroy holed seven birdies in a second-round 65 to move to 12 under par at the PGA Championship at Wentworth.
Ramsay says the world number eight is playing at a different level to the rest of the field.
"We all know how good he can be," Ramsay, one of four Scots to make the cut, told BBC Scotland.
"Sometimes even with his B-game he can really shoot a low number. He has great power off the tee but he is straight and that is important round here.
"Once you get your eye in with the putter there is definitely a low score out there."
Ramsay, 34, finished his second round eight shots behind McIlroy on four under and says he was content with his score despite some inconsistent play.
"It was a little bit of a rollercoaster which is quite unusual for me," the Aberdonian said. "I'm normally quite steady.
"I thought it was great fun. The course is playing brilliant and gives up chances when you play well, and when you are out of position you are going to struggle."
Gallacher and Warren satisfied
Also on four under par are compatriots Stephen Gallacher and 22-year-old Bradley Neil. Gallacher's round featured four bogies and seven birdies, four of which came at each of the par three holes.
"I hit four lovely shots," the 43-year-old said. "It is just one of those bizarre things that happens every now and again.
"I'm happy with that. Lots of birdies, just a few bogies. I left a few out there so I feel I could have gone really low today. I hope to carry that through to the weekend."
Neil's second-round 69 ensured he made the cut, but the Scot was disappointed to finish with two bogies from the final three holes.
"I made some unforced errors off the tee, the worst swings I put on all week at times where you just can't do that," he said.
"Sixteen, 17, 18 are dangerous holes. They don't suit my shape and I played them really poorly off the tee and you just can't do that round here.
"Now I can go into the weekend completely free and hopefully finish a lot better."
Marc Warren, 37, also made the cut after a level-par round of 72 left him one under for the tournament.
"I definitely played better than yesterday," Warren said. "My ball-striking was better and I holed a couple of really good par putts which are crucial when you are battling to make the cut.
"I birdied the 16th and then made par on the last two holes so I feel as if I'm getting closer to where I want to be."