Peter Hanson became the man to catch after a sparkling burst around the turn at the Volvo Golf Champions in Bahrain.
The Ryder Cup Swede followed birdies at the seventh and eighth with an eagle on the long ninth for the second day running and then made a 35 foot putt for another birdie at the 353 yard 11th.
Hanson moved to 16 under par with seven holes of his third round to play and was one in front of England's World Number Nine Paul Casey, the highest-ranked player in the field.
Casey turned in 34, birdied the 11th and then struck two mighty blows onto the green at the 587 yard 13th to set up a superb eagle.
Northern Ireland's Darren Clarke, who had earlier grabbed top spot by going to the turn in 32, was in third place two behind and one further back were Scot Stephen Gallacher and South African James Kingston.
The day began with former Open Championship winner Todd Hamilton equalling the course record and achieving the lowest round of his European Tour career with an eight under 64.
The 45 year old American, who switched to The European Tour after losing his US PGA Tour card, made the halfway cut with only a stroke to spare, but charged from 50th spot into a share of the lead for a few minutes at 11 under.
He equalled the record for the Colin Montgomerie-designed course established by Swede Johan Edfors on Thursday and repeated by Gallacher in the second round.
Montgomerie himself remained three under with a 72, while Padraig Harrington double-bogeyed the sixth and bogeyed the short next in a 73 that dropped him outside the top 50 on four under.
Ian Poulter, on the other hand, moved through the field with a 68 for seven under.
