Masters champion Danny Willett failed to replicate his blemish-free start to the BMW PGA Championship, but still moved top of the leaderboard with a second-round 68 at Wentworth.
In his first round in England since winning his maiden major title at Augusta, Willett carded a 66 to lie just a shot behind joint leaders YE Yang, Joost Luiten and Scott Hend.
With his approach game and short game working in unison Willett made six birdies in the space of seven holes to reach the turn in just 29 shots as the world No 9 made a blistering start on Friday morning.
At 12 under par he was five clear of Dutchman Luiten and on target to smash the tournament record for the lowest opening 36 holes set at 13 under in 2008 by Paul McGinley.
But the 28-year-old, who is targeting his sixth win on the European Tour, missed good birdie chances on the 12th and 13th while another shot went on the 16th after finding more sand off the tee.
Four bogeys on the back nine, including three on the spin from 15, took him back a few shots.
Willett finished in style though as a superb second shot on the par five last helped set him up for his second birdie after the turn to come home in 39 and finish closer to the chasing pack, but still three ahead of former US PGA champion Yang and Australian Hend on 10 under par, who were yet to start their second round.
Willett, who is is playing the event for the seventh year running, admitted the two birdies on the back nine were important although it was not the kind of display he was hoping for.
"I played great most of the day and then chucked a couple of horrid golf shots in there, and it was nice to make birdie at the last, two really good golf shots, composed myself quite nicely," the 28-year-old from Sheffield said.
"Again, you could have just chucked it and finished really poorly, but to make birdie on those was good. Shows a little bit of mental strength. But yeah, still not quite the back nine we were hoping for but 10-under par, you'd have taken it at the beginning of the day."
Asked about the impact of being timed for slow play along with playing partners Soomin Lee and Victor Dubuisson, Willett added: "It's tough to obviously double check yardage and stuff with blustery winds, a few tight flags out there. This place plays hard when the wind is swirling around. You'd like as much time as possible to double-check your numbers and make sure you're happy with what you've got.
"A couple of shots out there, we hit a little bit too quick and got the wind a little bit wrong. Got the direction of the wind slightly wrong off 14. You can't blame anything when you hit a couple of bad shots. But like I said, you'd take 68 at the beginning of the day."
Spain's Rafael Cabrera-Bello, Thailand's Kiradech Aphibarnrat and Joost Luiten were all in the clubhouse on five under, Luiten having challenged Willett for the lead before also covering the back nine in 39 to shoot 74.
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