SCOTTSDALE, Ariz. -- On a day when many Giants wanted to rush and leave town, left-hander Madison Bumgarner gave them a reason to linger, stare and imagine what could be.

Starting against the Los Angeles Dodgers in Wednesday's Cactus League finale, Bumgarner approached perfection in three shutout innings, allowing only Juan Castro's third-inning double in the Giants' 10-8 victory.

The Giants' top pitching prospect struck out four, including the formidable Manny Ramirez on three pitches. Bumgarner, San Francisco's first-round selection (10th overall) in the 2007 First-Year Player Draft, threw two inside fastballs and a slider to retire the Dodgers slugger.

Afterward, Ramirez was suitably impressed.

"He's nasty," Ramirez said. Told that Bumgarner's only 19, Ramirez replied, "Unbelievable. He has a fastball and a curveball. He's sneaky. He throws hard."

Bumgarner, who's likely to begin the season at high-Class A San Jose, had made two previous Cactus League appearances, throwing one shutout inning in each. But this assignment, which he received as Jonathan Sanchez cooled his scorched left index finger, drew more attention, since it was a start and it happened to occur against the Giants' chief rival.

"He has great stuff and great presence out there," Giants manager Bruce Bochy said. "You like the way he carries himself out there. He's a confident pitcher."

Bumgarner, who returned to the Giants' Minor League complex and wasn't available for comment, displayed a free and easy motion, reflecting why talent evaluators believe that he'll soon take his place alongside Tim Lincecum and Matt Cain in San Francisco's starting rotation.

Steve Holm, who caught Bumgarner, noticed Bumgarner's skill. The ball, said Holm, travels "so effortlessly out of his hand. It just jumps out at you."

As the Giants scrambled to dress for their flight to San Francisco, they could savor their 19-17 record, which contrasts sharply with the 9-23-2 mark they recorded last year. Meaningless as exhibition games might be, the Giants could entertain the notion of avoiding another 90-loss season.

"I thought it was important for us to win ballgames," Bochy said. "We talked about that before the first game. Last spring wasn't a good spring for us. Coming off a losing season, we wanted to change things. Hopefully it sends a sense of confidence throughout the club."

The Giants, who play four exhibition games in the Bay Area before opening the regular season Tuesday against Milwaukee at AT&T Park, finished the Cactus League with the best record among National League West clubs. Again, it's perhaps a hollow achievement. But for a team that has endured four consecutive losing seasons, any kind of winning is welcome.

"I don't think in Spring Training you can get a great indication of where a team's at," left-hander Randy Johnson said. "But if you could, then we would probably win the West."