
England’s 2010 BMW PGA Championship winner carded an early 66 to reach 13 under at the halfway stage, and none of the afternoon starters were able to catch him.
The 39 year old has had something of a subdued season to date, with a fifth-place finish in France his best result of 2011 so far.“I hit it perfect. I think that you have to be positive around this course, and if the wind gets up a little bit, it can be a little bit more testing. You've just got to hit your wedges close and definitely get the putter going, that's the key.
“It's been a great two days. It's not been a brilliant year overall, but I always feel good coming around this course and enjoy playing in Portugal. I'm delighted with the two days.”
Welshman Rhys Davies, first-round leader James Kingston and Chilean Felipe Aguilar are one behind Khan, with Swede Christian Nilsson and England’s David Dixon on ten under.
At 51st on The Race to Dubai, Davies can confirm his place at the season ending Dubai World Championship with a good showing on the Algarve.
And the former Trophée Hassan II winner impressed with seven birdies in a round of 67 to be 12 under at the halfway stage.
The 26 year old will certainly appreciate the late start on Saturday, with Wales facing France in the semi-final of the Rugby World Cup at 9am.
“I think we have a great chance,” said Davies. “We have a really tough team to play against, there's no doubt about it. I think the French are quite unpredictable.
“Thomas Levet was trying to tell me how dominant they were earlier, but I'm having none of it. I back my boys and I think they are great stuff. They have a really great team chemistry going, it seems, and they are playing some really good rugby. We are fully confident on that we can turn them over tomorrow.”
South African Kingston threatened to match his sparkling opening 64 when he began with three birdies in his first four holes, but there were only two further gains separated by a bogey at the fifth.
“I'm not beating myself up,” said the 45 year old. “I played nicely out there. It was one of those days where I could have posted a decent round again, but it's never easy to do it after a low round the first day. Like I say, I played solid golf and I'm one behind.”
Like Davies, Aguilar is looking to book his place in Dubai in December – and at 61st in The Race to Dubai he is currently one place outside the cut-off point.
“I'm in good position,” said Aguilar, who mixed eight birdies with two bogeys. “This is where you want to be. I like to hunt from behind, especially on the weekend.
“I have nothing to lose - I think I'm playing well this year. I have my card and I want to get into The Race to Dubai.”