"It's strange for us to think that he's 23," catcher Buster Posey said Monday before Bumgarner made his Cactus League debut with two shutout innings in San Francisco's 9-9 tie with the Chicago White Sox.
Such remarks about Bumgarner have been commonplace since he was promoted to the Giants in 2010. They've typically been prompted by his mature demeanor and poise on the mound. This spring, Bumgarner's savvy, a closely related trait, has commanded attention.
"I think he's figuring out that there's going to be certain adjustments he's going to have to make throughout the course of the year," Posey said.
That became evident against the White Sox. Bumgarner continued to display a slightly but significantly altered pitching delivery. From the windup, he swiveled less toward second base than he previously did.
"I'm definitely going to stick with it," Bumgarner said. "I didn't plan to start turning so much last year. It just gradually became more and more. Before I knew it, I was spinning around like [Hideo] Nomo."
Fellow left-hander Dan Runzler marveled over Bumgarner's ability to adapt.
"You don't look at him as a 22-, 23-year-old. You look at him as a guy who's pitched in the Majors for a while," Runzler said of Bumgarner, who already has started 84 regular-season and six postseason games in his career. "It shows when he's on the mound -- not just the way he competes, but how he sticks to his plans, sticks to his strengths, how he attacks hitters. It's fun to watch. Sometimes you have to remind yourself that he's that young."
Bumgarner's unwanted range of motion partly prompted his ineffectiveness as the 2012 campaign concluded. Though he finished 16-11 with a 3.37 ERA, he posted a 2-4 record with a 5.73 ERA in his final seven regular-season starts. Bumgarner then lost his first two postseason outings, yielding 10 runs and 15 hits in eight innings.
The Giants rested him for 10 days, enabling him to work more closely with pitching coach Dave Righetti. Curbing his spinning was among the flaws they addressed. Refreshed and retooled, Bumgarner started Game 2 of the World Series against Detroit and surrendered just two hits in seven innings as the Giants triumphed, 2-0.
"It helped a little bit just to contribute instead of making it seem like you're messing it up for everybody, every time you go out there," Bumgarner said. "It felt good to help us. But I knew I wasn't close to where I needed to be. I had a lot of work to do."
So the Giants' No. 2 starter entered Spring Training concentrating on gaining more consistency with spotting his fastball outside, as well as commanding his changeup and curveball. He'd also like to hold runners on base more efficiently.
Bumgarner's credentials suggest that he'll achieve his goals. Hall of Famer Rube Marquard is the only other pitcher in Giants history to win at least 16 games in a season at age 23 or younger.
"We talk a lot about pitching, anywhere from mechanically to mentally," Runzler said. "He's definitely wise beyond his years, as far as how he can judge hitters and what he's trying to do with a plan."
"I've caught him before where he's had a really good move to first base," Posey said. "Maybe with less of a turn, he'll get some of that old move back. Because he's pretty deceptive to the runners when he's right."
Bumgarner's increased knowledge and improved mechanics complement one of his long-established traits: Extreme effort.
"We all know that he's a competitor," Posey said, "and when it comes down to it, no matter how he's feeling or if things haven't been going right for him, you feel like every time he's on the mound, he has a shot to win. Because he's going to give everything he has to be better than the guy in the batter's box."