(MENAFN - Kora)
The American shared the overnight lead with Jordan Spieth, but eased to 13 under on a tough day for scoring which included play being halted due to high winds.
Walker produced a four-under 67 on the Monterey Peninsula Country Club course to be in complete control of the PGA Tour event.
The 35-year-old is the hot favourite to claim his third win on Tour and second of 2014 having taken out the Sony Open in January.
New Zealand's Tim Wilkinson (69) and American Hunter Mahan (72) were on the same course and sit at seven under in a tie for second.
Richard H Lee managed an even-par 72 on the Spyglass Hill Golf Course to be outright fourth at six under.
Wind gusts of close to 64km/h led to officials stopping play as several balls moved after being marked by players.
The greens were watered and play resumed before being stopped again later in the day due to darkness, with several players yet to finish their third rounds.
Spieth struggled with the conditions and is five over for the day through 15, down in a tie for 11th at four under.
Four-time winner Phil Mickelson is in contention at five under and tied for fifth alongside five others.
Blake Adams, Kevin Na, Ryan Palmer, Pat Perez and Jim Renner are equal with Mickelson after solid rounds.
Walker holed birdies on the second, fourth and seventh holes to go with a bogey at the par-four fifth.
He was solid with pars during the back nine before adding birdies at the 16th and 17th holes to complete the day's best round.
Jim Herman is the best-placed of those yet to complete their rounds, tied for 11th through 17.
The third round will be completed on Sunday, deciding the 54-hole cut line.