Kevin Na carded a 1-under 69 in third-round action at the Charles Schwab Challenge on Saturday, good enough for a two-shot lead with 18 holes left to play.
Na's edge could have been bigger if not for a costly double-bogey on the par-5 11th, the lone blemish on his scorecard. His three-birdie performance put him at 9-under for the tournament.
Spieth's putter remained scorching hot in Round 3. He dropped birdie putts of 29, 20, and 37 feet to put him at slightly over 434 feet of putts made through 54 holes. He's 117 feet away from setting the record in the ShotLink-data era (since 2004), according to the PGA Tour's Mike McAllister.
Finau posted a 1-over 71, his worst round of the week by three strokes.
Canada's Hughes snuck into a tie for second by posting an early 5-under 65. He's searching for his second career PGA Tour victory.
Jonas Blixt, the 54-hole leader, shot a 4-over 74 to drop into a tie for ninth and four shots off the pace.
The low round of the day belonged to Charley Hoffman, who fired a 7-under 63 to climb within three of the lead.
Na and Hughes tee off in the final pairing at 2:05 p.m. ET on Sunday.