Dufner's unspectacular but solid round was enough to allow him to maintain a one-shot lead over three competitors at 8-under 202.
The field behind him underwent some big changes Saturday, however, as J.J. Henry and Jason Day charged up the leaderboard, each with a round of 3-under 67.
The forged a second-place tie with Dicky Pride (69) at 7-under 203.
Vijay Singh posted a 4-under 66 to grab sole possession of fifth place at minus-6.
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