France's Alexander Levy had five straight birdies in the middle of his round and finished with a 7-under 65 on Thursday to take the lead in the BMW Masters.
Levy began the birdie run on the par-4 ninth on Lake Malaren's Masters Course. He won the Volvo China Open in Shenzhen in April for his first European Tour title and took the rain-shortened Portugal Masters this month.
The tournament opens the four-event Final Series. The World Golf Championships-HSBC Champions is next week, also in Shanghai, followed by the Turkish Airlines Open and World Tour Championship in Dubai.
Belgium's Nicolas Colsaerts was a stroke back along with Argentina's Emiliano Grillo and France's Romain Wattel. Northern Ireland's Graeme McDowell topped the six European Ryder Cup players in the field with a 67. Gleneagles teammates Jamie Donaldson and Thomas Bjorn shot 68.
Defending champion Gonzalo Fernandez-Castano of Spain had a 72.