Boosted by the hot start, Bowditch continued to display an exquisite short game, recovering from some poor long shots to notch just one bogey on his way to a four-under-par 68 at the TPC San Antonio.
"I didn't hit the ball real well today at all," Bowditch told reporters after posting a 12-under 204 total with one round left.
Matt Kuchar (65) carded the lowest round of the week to storm into a tie for second on nine-under with fellow American Andrew Loupe (70), who bogeyed the par-five 18th.
The event lost its biggest attraction when five-time major champion Phil Mickelson withdrew on his 11th hole, citing a pulled abdominal muscle. His decision seemed purely precautionary, only two weeks before he shoots for a fourth green jacket at the Masters.
Bowditch had never held an end-of-round lead in 110 starts on the PGA Tour before Friday, so his start to the third round was a perfect tonic to calm the nerves.
He chipped in for birdie from 25 feet at the par-four first and then holed out from nearly 30 yards for eagle at the par-five second, leading comfortably for the rest of the day.
"The chip on the first was pretty simple but the one on the second I was just trying to get around the hole and luckily it dropped in," said the 30-year-old, who hit only eight greens in regulation.
"I don't even want to know how many greens I hit but I know it wasn't many. Hopefully tomorrow I will hit a few more fairways and a few more greens."
Bowditch was a champion junior in his homeland but it has taken him a while to find his feet on tour. He is ranked 339th in the world and while he will start the final round the man to beat, world number 11 Kuchar is brimming with confidence.
Kuchar, the only player among the tournament's top seven with more than one tour victory, had eight birdies in his round. He sank a bunker shot at the first hole for birdie and also closed in style with a tap-in birdie at the last.
"It's an exciting position to be in," said Kuchar, who has won five times on tour.
"My game's in really good shape. The first two days I left a number of shots out there (but) today was a much better performance as far as scoring."
- Sports & Recreation
- Matt Kuchar