Williams, a Waipahu High graduate, had the shells around his neck Friday night, when the 21-year-old rookie pitched the first shutout of his major league career. The necklace is a constant reminder of his Hawaiian roots — and a tribute to his mother, Deborah, whose death from cancer two years ago has inspired Williams to feats he never imagined.

"She gave it to me," Williams said, rubbing the shells between his fingers. "She's not here, but she's always here with me in spirit."

In just six starts with the Giants, Williams (2-1) has provided a remarkable lift to the first-place club's inconsistent pitching staff. After being called up from Triple-A Fresno twice this season as a stopgap starter for injured regulars, he seems determined to stick around.

Williams has improved in every start, culminating in consecutive victories over the Oakland Athletics in his last two appearances.

San Francisco rookie pitcher Jerome Williams and catcher Benito Santiago were greeted by teammates after a win over Oakland Friday night. Associated Press

"It's crazy," Williams said. "I came into this season thinking I'd get a September callup."

Most pitchers spend their entire careers searching for the control Williams has exhibited during his first month in the majors, but Williams doesn't seem to think it's anything special. His manager disagrees.

"Hitters really aren't that good if you throw strikes," Felipe Alou said. "There was a time (on Friday night) that I couldn't believe. Everything was a strike, and they weren't just down the middle of the plate. They were on the corners, in and out."

Alou first thought Williams might be something special during a preseason exhibition game in Fresno last March. When Kurt Ainsworth was knocked out of the rotation with what turned out to be a broken shoulder blade in early June, the Giants recalled Williams to make an emergency start against the Twins.

Williams pitched into the seventh inning, and hasn't looked back.

"He really injected a degree of confidence when it comes to the rotation," Alou said. "(Damian) Moss was struggling, and Ainsworth was hurt. He was awesome against us in Fresno, and he's been more than we hoped up here."

Williams says his control didn't begin to develop until he was pitching for Double-A Shreveport two years ago — the same year Deborah died after battling breast cancer for six years.

"Back in high school, I was a hardheaded little kid," Williams said. "I didn't listen to the coaches. When I got up to Double-A, I tried to become a control pitcher."

Alou hopes Williams will maintain consistency in his control — and so far, that doesn't seem to be a problem. Williams threw 31 pitches in the final three innings of his shutout — and 28 were strikes.

"He was awesome for a rookie," Oakland's Mark Ellis said. "He put it wherever he wanted it. We were all impressed."

As he mowed down the A's Friday night, Williams' white necklace was visible from the upper deck at Pacific Bell Park. His brother, Glenn, retrieved it from their mother's grave after his first necklace broke while he was pitching in Chicago earlier in the month.

A few shells salvaged from the broken necklace are lodged under the brim of his hat.