English duo Paul Waring and David Lynn shared a second round lead with South African Hennie Otto at the Portugal Masters in Vilamoura on Friday.
Still struggling with a virus which hampered him during last week's Seve Trophy, Lynn had shared a seven-way lead overnight and held his advantage with a second straight 65 following four birdies and an eagle.
Playing in the same group, Waring and Otto recorded 14 birdies and one eagle between them to each finish 12 under par.
Waring, playing on a medical exemption after an operation on a serious wrist injury, shot an eight-under par 63 and Otto a 64.
"I am not going to put too much pressure on myself, I've had a medical (exemption) all year so it's nice to get back into a proper category for next year," said Waring, who is currently 86th on the Race to Dubai.
Austria's Bernd Wiesberger completed a 65 to lie one shot off the lead on 11 under alongside Scotland's Chris Doak, who had five birdies and an eagle for 64.
"I'm very pleased," said the 35-year-old Doak, who is 112th on the Race to Dubai with only the top 110 after next week's Perth International keeping their full playing privileges for next season.
South African Justin Walters was a further shot back after at round of 63.