REUTERS: Marc Leishman carded a solid three-under-par 68 to extend his lead to five strokes after the third round at the BMW Championship outside Chicago on Saturday.
Leishman, who started the day three in front, posted a 19-under 194 total with one round left at Conway Farms in Lake Forest, Illinois.
Fellow Australian Jason Day and American Rickie Fowler both shot 70 to share second place on 14-under, with Englishman Justin Rose (66) alone on 12-under.
World number 22 Leishman is seeking his third victory on the PGA Tour.
The BMW Championship is the penultimate event of the PGA Tour season.
(Reporting by Andrew Both in Cary, North Carolina, editing by Gene Cherry)