Defending champion Alex Noren hailed “the best round I’ve ever seen” after playing partner Rory McIlroy took command of the BMW PGA Championship at Wentworth.

Noren carded a course record of 62 in the final round last year, but was nevertheless happy to heap praise on McIlroy’s flawless 65, which gave the four-time major winner a halfway total of 12 under par and a three-shot lead over England’s Sam Horsfield.

“That’s the best round I’ve ever seen. I’m about to quit golf I think,” said Noren, whose own 68 left him five shots off the pace on seven under alongside Robert Rock and Kiradech Aphibarnrat.

“It’s hard to draw off it when it’s that good. It’s tough because it’s almost like you’re trying to play better than you need to when you see that. I really wanted to get the honour and be first on the tee and then you don’t have to hit after that 330-yard driver or 300-yard three-wood.”

McIlroy’s more measured assessment reflected the fact that he missed good chances on the first three holes and failed to birdie the 17th and 18th, both par fives, for the second day in succession.

“There’s still a couple of loose shots in there, like the one on 18 (which plugged in a greenside bunker), but overall it was a great round of golf,” McIlroy said after matching his career-low score at Wentworth, although a previous 65 in 2009 was before the course changes the following year.

“I had everything sort of firing today and it was nice to take advantage of the opportunities I gave myself. All you ask for is giving yourself a chance every week.

“I could go out and shoot two 65s at the weekend and get beaten so you can’t expect to win. All I expect to do is go out and control what I can control. Every tournament is a big tournament but the more I can play well and the more confidence I can build going into those majors the better.”

McIlroy – who confirmed he is no longer working with putting coach Phil Kenyon – got the ball rolling with a birdie on the par-five fourth, before picking up further shots on the seventh and ninth to reach the turn in 32.

The 29-year-old then rattled off four birdies in succession on the back nine and was five shots clear before Horsfield fired four birdies in five holes from the 12th.

The Orlando-based 21-year-old, who is a protege of Ian Poulter, gained his European Tour card by winning the qualifying school by eight shots last year and has already recorded two top-four finishes in his rookie season.

“I think any time you’re playing on the weekend and you’re up there near Rory, I think you’re going to be doing pretty well,” Horsfield said. “Whoever I end up playing with I’m going to go out there and give it my all.

“I’ve lived in America since I was five but I do feel English and there’s no doubt who I’d play for in the Ryder Cup. It’s pretty cool to be able to play in an event like this.”

European number one Tommy Fleetwood birdied the last three holes to shoot 66 and lie four shots off the lead, while playing partner Poulter did the same in his 67 to finish three under.